usually at the expense of one or the other, usually cars.

FWIW I think that is a fine trade-off. I think people don’t truly realise how poorly cars scale until they take a really large step back and take a holistic view on infrastructure- which is inherently difficult for most people as they are so close and bought-in that they can’t even conceive of life being different than what they’re used to.

And they reach for exceptions to prove the requirement, when less cars in cities frees up the roads for those that truly need it (LGV and disabled access, but slow thus disincentivised unless actually required and this less likely to cause accidents).

It's not necessarily at the expense of cars; the people riding bicycles on the bike lane are no longer driving cars blocking the way ahead of you. Since bicycles use space more efficiently than cars, this can actually be a win for both the cyclists and the remaining drivers (who now have one less lane, but even less traffic). However this only happens if cycling adoption is high enough, which is why the bike routes have to be well connected.

Sometimes it doesn't even require sacrificing a lane, because many North American cities have lanes that are wildly larger than necessary or even appropriate given the posted speed limits. The lanes can simply be narrowed, and then this also causes the drivers to naturally drive at safer speeds, reducing traffic accidents, speeding tickets, and the unplanned delays that those both cause.

The bike lane space has to come from somewhere, parking space for bikes has to come from somewhere, intersections have to be set up to disadvantage one for the other.

Street space really is zero-sum, though more people in bikes and out of cars free’s up so much infrastructure that it can make less space work even better for cars- I’m sure urban designers are aware of this.

The major issue I presume that is faced in urban design is how to handle people coming from far away, the regional hub/spoke design (with train stations around a radial that have good parking allowing train access into the city) is not something actively pursued by advanced economies for some (presumably good) reason.

The bit you are missing is the space efficiency. Cars take up the most space by a large margin and getting people into more dense forms of transit (anything else) frees up space to be more efficiently used.

> The bike lane space has to come from somewhere

> though more people in bikes and out of cars free’s up so much infrastructure that it can make less space work even better for cars

Yes, you've reiterated my point...

In Chicago, more people ride the Ashland bus than drive down Ashland every day. We still couldn’t take a lane for bus rapid transit.

People are already stupid, put them in a car and their brains start leaking out of their ears.

And how many do it thoroughly, not just in small parts?