People have this weird idea that if SFH-zoning was abolished, that a midrise apartment would pop up next door. I highly doubt that scenario would happen. What you would likely see is many areas stay as SFH, but in some areas where it makes sense or demand is high enough, you'd start to see more missing middle housing: duplexes, townhouses, triplexes, etc... And near transit, you could encourage midrise buildings. Those that want a SFH can still have a SFH, and those that want higher density living and walkable communities can have that.
The bias to SFH has been baked in by decisions made 2-3 generations ago - it's not necessarily people's default preference. We've had years and years of a one-way ratchet that has restricted housing and baked in suburban sprawl. And now the landowners have a vested interest to keep it that way, since we've baked so much of family wealth into owning a home as a nest egg, instead of seeing a home first and foremost as a place to live.