A little girl was run over and killed at a location where Caltrans and SFCTA now want to pump in more high-speed traffic through a freeway ramp widening. Then they wonder why Vision Zero is failing
Politics is inherently multi-dimensional. Car-brain vs walkability is mostly orthogonal to conventional left vs right politics.
Chuck Marohn of Strong Towns has always made a conservative argument against car centric infrastructure - emphasizing that it's not fiscally sustainable, that the other approach worked for literal millennia, and that cities should be allowed to be complex and evolve bottom-up rather than via top-down government mandates.
And there's tons of liberals who have fully bought into car-brained thinking.
Honestly, framing it as left vs right is a bad strategy. We should emphasize how sprawl is bad regardless of which side of the aisle you're on. It's expensive, it requires government overregulation, it's bad for everyone's health, it's bad for the environment, etc.
Conservative in politics means resistance to social change. Resistance to infrastructure change is colloquially called NIMBY. A conservative in the US would generally be pro more roads, as that's doing more of the same.