> You solve problems of scale at scale.
Yes. One good step would be to allow density everywhere so more people who want to live in dense environments can afford to do so. After all, there's more demand for walkable places than there are walkable places: https://cityobservatory.org/the-myth-of-revealed-preference-...
> make it actually better, quieter, cleaner, and cheaper
Trying over here. My local government is not very amenable to this, unfortunately.
> it takes up to two hours to go a few miles by any mode of transportation
In a city that actually cares about efficiently moving people seriously, that'd be absurdly slow. It takes far less time than that to bike a few miles. Yes, most American cities don't have the infrastructure for that. Again: trying.
But all that aside:
> You don't tell people to lower their energy, you build desirable technologies that use less energy automatically, and most importantly, raise the energy consumption level that is sustainable by building more carbon-free power ASAP.
This is an important part of the solution, yes, but time is not on our side here. I think it's foolish to think that we can reduce our emissions as much as we need to while maintaining our lifestyles exactly as they are. Maybe if we'd taken the problem seriously decades ago that would have been the case, but now it's going to involve at least some level of inconvenience.
An example: it takes a long time for all the cars on the road to turn over. Even if we assume that electric cars will become massively more popular and available in the next decade, and even if we assume that 100% of the electricity to power those comes from green energy, we still wouldn't be on track to halve emissions from passenger vehicles by 2030, because a significant percentage on the vehicles on the road would still be gas powered. Some element of this is going to have to involve less driving. And that's just one source of emissions.