both are good

Okay, so, here's the thing: car-centric design is the reason our cities suck. You're 100% right that suburban sprawl in the enemy of good public transit, and that's just one part of why it's going to be critical to push for good urbanism in our city designs. Bad urban design that enforces car dependency is the enemy of so many of our goals, including climate change. Here's just a short list of the stuff it fucks up:

• City Finances. Ever wonder why North American cities uniquely seem to sprawl out, with rich suburbs on the rims, and then rot from the center outward? It's because the sprawled out car dependent suburbs don't pay for themselves in taxes, and the more of them you build, the more you erode the ability of the city to stay solvent and pay for basic things, let alone nice things.
• Temperature: parking lots and wide ass roads basically work as giant heat batteries. Also related: they make your area more prone to flooding by reducing the permeable surfaces in your city.
• Public transit: basically, by setting a ceiling on the possible number of riders in a given catchment area for transit, you permanently kneecap your transit system and keep it broke and struggling forever. That means that your transit system will have fewer useful stops and lower frequency schedules, which make it even less useful to use, which means less riders, and so on and so forth.
• traffic: look, twenty people riding a bus takes up the space of a bus, which is, at a guess, about three realistically spaced cars (which at an average of 1.5 occupants per car, means 4.5 riders). To meet just the twenty people on a bus (NOT the bus' capacity!), you need 20/1.5= ~13 cars / 3 car spaces per bus = the equivalent space of four busses. That is, not even with the bus at capacity, you need four times as much space to move the same amount of people in cars. If it comes to walking, bikes, and trains, it's a total fucking laugh-out. There's no way around it, cars ARE traffic. If you want a better driving experience, you need fewer cars on the road, not more. More lanes does not fix the problem.
• finances pt2: the city also has to spend a lot more money constantly rebuilding roads due to how quickly cars demolish the infrastructure they use. This is actually going to be MORE true with EVs, since they're heavier. Yes, that also means busses cause a lot of damage too, but you can prevent a lot of damage by just making your city walkable and bikeable (or building the damn trains). Because you need a place to keep the car when you're not using it, cities also end up losing a lot of space that would otherwise be used to host people or businesses to host idle cars sometimes (and just sit empty the rest of the time).
• public health: yeah, smog, okay, everybody knows that. Car centric infrastructure also contributes meaningfully to our obesity epidemic by ensuring that people never really have a reason to walk or bike anywhere. It's bad for our mental health because you lose out on opportunities to run into and converse with other people, like your neighbors, because you're driving instead of walking, biking, or taking the bus. It's bad for everything alive because car tires, even from EVs, are responsible for 40% of oceanic microplastics. You know that 99% of samples seafoods are contaminated with microplastics? There's a pretty good chance you're eating a side of tire dust with your Camerones a la diabla. You're also breathing it in and just kind of existing in a cloud of microplastics tire dust.
• Climate: duh
• Economic opportunities and housing: car centric urban development doesn't necessarily require that single family homes are the only thing that gets built, but it certainly seems to encourage it. Even if you are building apartments, it means that at least the same amount of space (usually more) that people are living in gets set aside to store their cars. That makes it more expensive for everyone, and inhibits the number of housing units that can get built. Car centric infrastructure also means that the bulk of the economic development in your city is going to be big box marts and drive throughs that are culturally bankrupt and extract wealth from your community. When cities allow more mixed use development, neighborhood commercial development, and walkability, there's many, many, many more opportunities for small and medium businesses that generate and keep wealth in your community.
• cost of living: it's really hard to beat the value of good public transit or a $200 uninsured vehicle being your primary mode of transport. Instead, we all end up paying an order of magnitude more to buy, maintain, fuel, and insure our own private vehicles. Oh boy, I sure do love being free to pay $700 a month to pay for my car and keep it safe and legal instead of $70 for all the train rides I could ever ask for, because that would be communism. (That's not directed at you, btw)
• safety: look, it's probably not great getting hit by a bike, but I'd rather my kid get hit by a bike than a Ford F-MINIVAN-IN-A-TRENCHCOAT-50. The more people we get out of cars and into public transit or bikes, the safer our streets will be to use.
• equity: look, not everyone can drive. Some people can't afford it, others are prevented by physical or mental ability, and still others are shut out by government safety requirements. I've personally seen it two or three times where an old person living in a suburb with no access to services in walking distance gets their license pulled for safety reasons, and it's basically a guarantee for a premature death. They either go to a home and lose their independence, or they suffer and stress until they die. Likewise, it means that our medically disabled people are functionally second class citizens in our transit system; people who are the MOST dependent on being able to make government and medical appointments, mind you. That's fucked up.

A lot of people in rural parts of Europe get around by bus and train.

They're only not viable if you genuinely live in the middle of nowhere.