Not all new automobiles are fuel efficient, some still get single digit miles per gallon gas guzzler ratings with big V8 engines that suck down fuel while belching out smog forming climate changing emissions, though automakers are shying away from monstrosities on wheels to embrace fuel economy benefits of applied technologies, turbo-charged four-banger engines even in SUV's now, even 3 cylinder turbo in something as superlative as the GR Corolla AWD rally art master class example :)
If I didn't have a Corolla Hybrid Sedan LE, I would be lusting after & ready to pull the purchasing trigger on GR Corolla, bit it gets middle twenties fuel economy & requires premium fuel, & turbo charged with so many PSI that Toyota set a record as an automaker by boosting GR Corolla engine to higher levels of boost than any production car engine ever in history, though stressing the engine with hot pressure like that could result in shorter engine life long-term & Lord knows if I purchased a GR Corolla I would drive it until it was ready for end-of-life scrapping in 30 years.
Today you can buy an SUV like a Rav4 Hybrid that gets over 30MPG, the Prime (Plug-in Hybride) gets almost 70 MPG as electrical energy replaces gasoline allowing electric trips around town commuting, while the 496 HP AWD system of Rav4 Prime provides both astonishing performance & towing capacity, but also super ultra-high fuel economy record holder with proportionately lower emissions.
Need something for off-road or unimproved roads with rocks & ruts & pot holes, the Landcruiser by Toyota the OG of SUV's, that is my all-time most favorite vehicle of any kind, other than Prius by the millions. Better than Pre-24 G-Wagon, the Landcruiser so durable that even the oldest examples are still operating daily in developing economies where road quality lesser & where people can only buy used older vehicles since they don't have enough money to buy a newer model year, so Toyota's lineup since way back when offering legendary reliability means anyone on any budget can get a reliable used car.
The Landcruiser by Toyota not fuel efficient, its strong, durable in all conditions, holds up well, robust, long lasting, excellent off-road, great for pulling trailers or boats or utility loads or cargo, for personal or business use cases, but it uses a lot of fuel & does not benefit from their epic hybrid synergy drive technology developed far more recently for sales in markets where emissions regulations & fuel economy target regulations like CAFE corporate average fuel economy, USA, favor higher fuel economy model sales so the automakers does not have to pay gas guzzler penalties, & more profitable as a result.
Urban 2 wheel fun ambitions, 2025 Honda Grom gets 160+ MPG, you can drive it 40 miles round trip to work & back all week on $5 worth of gasoline, if its about $3.20 per gallon, more or less depending on local fuel prices, but there are no engine based automobiles getting over 150 MPG, the only one that ever did was the VW XL1, but that limited production pissing contest proof of concept low volume might as well be an aerospace helicopter. They all sold to executives of VW before the production was finished.
Just like Jay Leno's custom turbine engine car, if you can throw down hundreds of thousands of dollars, or up to millions of dollars, you can get a titanium floss fiber carbon aramid fully enclosed human battery electric made in Switzerland 300 MPGe that goes 100 MPH using tiny amounts of energy, aerodynamic drag lowest possible like a bullet shape riding on two hard wheels tucked under it, for $70K that's actually a real vehicle, I have no idea the name anymore, forgot long ago, cause even back then a loaded Model S from Tesla was less costly & far more interesting for us in America where a car, truck or SUV the only practical way of getting around as a full functioning working person.
I dog on BEV because lithium-ion batteries fade, meaning that new EV with 350miles of initial range, becomes more like 250 miles of range after 8 years, then its energy storage battery keeps losing its ability to hold a charge, until range only 100 miles after 18 years, then its $20K to replace the old lithium ion battery, since society moved on to sodium ion & solid state batteries since then, so CATL still makes cells for the old stuff but the price higher since economies of global scale production are no longer at work making old school li-ion batteries by the billion, the high cost of cobalt making that less feasible so all the battery makers embrace Na-ion & Al-ion & Mg-ion, as they are making use of Earth Abundant cheaper minerals & offering similar performance as the best older generation li-ion batteries.
Someone astute about design of my daily driver a 2022 Corolla Hybrid Sedan LE might point out, your HEV battery Li-ion, about 4AH 207.2 volts, 3.7v cells in series of 56 cells, about 800 watt hours energy storage for brake regenerative energy capture & acceleration assist that enables me to get over 53 MPG when driven in Normal, maybe 44 MPG fast driving in Sport, & 60 & 74 MPG hypermiling in ECO, making it more fuel efficient than our 2020 Yamaha MT03 motorcycle with 321cc offset twin engine refined in R3 for 12 generations :) That motorcycle goes 0-60 MPH in 4.3 seconds & has a top speed of 112 MPH, about 40 HP & 20 ft-lbs torque, its ergonomic comfy seating upright & idle for intercity commuting in fair weather engaging manual transmission, wind in face, far more limbic analog than riding in a car, unless is a slingshot or something fun like a Mazda Miata with the top down :)
Sure, the Corolla Li-Ion traction battery will fade, but HSD computer keeps the traction battery in Toyota Hybrids between 30 to 80% long life mode charged, which extends the useful life well beyond 15 years before this $3000 to replace battery needs replacing long term. Automotive grade li-ion used in Toyota Hybrid made by Panasonic EV ultra-high quality, far more durable than flaky electronics LiPo batteries in your smartphone that fade hard within 3 years & are more like the long lasting li-ion batteries used on space satellites. 2ZR-FXE engine in Corolla Hybrid 22 MY similar to one used in 3rd Gen. Prius since 2009, iteratively improved repeatedly more than 7 times before adapted for use in Corolla Hybrid. See, Toyota sells 10 Corolla Hybrids for every 1 Prius sold, so that helps them achieve CAFE targets.
Boeing 787 Dreamliner gets 67 MPG per passenger, nearly double the fuel economy of A321
A premium efficiency Mini-Split Heat Pump installed professionally gets COP 7.1 incredibly
Rav4 Prime or Prius Prime, 70 MPG + a little electricity
These are all examples of superlative energy economy at upfront higher cost, but less expensive long term as the super-efficient design uses half the amount of energy when operating, so savings from lower operating costs more than make up for the increased purchase price, in the end more than paying for the premium efficiency devices with an ROI of ~3.2 years before lower operating costs makes it cheaper with lower total lifetime costs of ownership calculated when planning purchase of efficient devices.
Energy Efficiency means doing more with less energy, lower emissions, saving more long term, lower net lifetime environmental impacts all said when evaluating all costs of the entire lifecycle & operations & ownership of such things. From data center optimizations to lower operating costs in factory, to making fuel efficient vehicle purchasing choices, or buying energy efficient appliances or windows with better insulation & gas filled & low-e film applied, so they keep your home cooler in the summer & warmer in the winter, while lowering your utility bills by helping your home use less energy.