In Seattle, if I want to get from a suburb on the east side into the city, during ANY trafficked time, it's going to be at least 2 busses (usually crowded, late, or full, so add another ~1), a decent amount of walking, and a 1.5-2 hour total trip. This compounds with the fact that many of the fringe buses only come once every half/hour, and not at all on weekends.
Compare this to a city that had proper infrastructure to start, Philadelphia. I lived a comparative distance, and the population is MUCH higher and denser. But a 5 minute walk and a single 20-30 minute train ride put me anywhere I wanted in center city. While Seattle "has light rail" it's an honest joke next to the coverage in the north-east.
As such, there's _no option_ to tax balance, it would end up being highly regressive punishing those forced to live further out and with no option but to use a car. The vicious cycle comes into play as the increased car traffic makes public transit less emphasized, convenient, and more of a perceived negative, leading to increased car traffic, etc etc. (compounded by less people wanting to take the tax burden they don't see a personal benefit to; there are a few different "tragedy of the commons" type effects in this mess.)
If we had trains that could get me to work like the sister post says about Stockholm's, no need for additional motivation, I wouldn't own a car for an instant, and didn't until my mid/late 20s when I left the east coast, but that's not the reality of the cities we've built, and now we're in a bit of a hole that I'm not sure how to incentivise people out of.