I’ve lived and worked in a few cities: Cleveland, OH, Seattle, WA, San Francisco, CA (worked, not lived), and here.
Cleveland’s public transit is crap. Though my mom rides it every day to get to work.
San Francisco, in comparison, was pretty ok, but the locals called it crap.
Seattle’s I actually used, but again, most of the people there thought it was crap. Where I lived was right off one of the main arteries so it was OK for me, but if you wanted to go from one neighborhood to another you’d generally be screwed. (Lots of north-south routes to downtown, few east-west connecting neighborhoods)
The only places that public transportation works is in places with high population density. The place I lived in Seattle was in the Greenwood neighborhood. The average lot size was around 0.1 acre; we were on 0.07 acre. That density wasn’t sufficient to make public transportation viable for most of the people living there.
If you look at places where public transit works, you’re basically left with New York in the US (even though they suffer majorly from aging infrastructure), and some European cities, primarily London and Paris, though many other places work pretty well as well. The key to that is those cities grew up in an era without cars so they are necessarily dense.
Residential Nashville, even in places like East Nashville, has lower density than what I had in Seattle, and that wasn’t dense enough.
I’m not saying I wouldn’t want busses, but it’s not practical with the way things are built here.
The only way to get it to be practical is to increase population density. Increasing population density involves redoing neighborhoods. You know the tall-skinny houses that go in and people complain about? Yeah, that’s population density.