It's worth noting that, at least for bart, the reason that it is facing bankruptcy is precisely because it was mostly rider supported and profitable, and not government supported.
When ridership plummeted by >50% during the pandemic, fixed costs stayed the same, but income dropped. Last time I checked, if Bart ridership returned to 2019 levels, with no other changes, it would be profitable again.
You can't say that BART "is facing bankruptcy is precisely because it was mostly rider supported and profitable, and not government supported" when it is very obvious that BART would be in a much worse situation if it had had more government support... because all those governments are facing massive budget deficits right now.
BART has already been bailed out by the state, twice. It has already failed, twice. It very much needs to reduce the level service it provides if it wants to be sustainable, or seek other forms of revenues while we wait to see if ridership returns. Many have suggested BART explore the SE Asian model of generating revenues by developing residential housing, which seems fairly straightforward.
If ridership never returns, then we ought not continue throwing good money after bad, and we ought to adjust the level of service to meet the level of revenues. Obviously the main problem here is that it's literally illegal to just build high density corridors directly adjacent to the transit stations... which is what we ultimately need to prioritize.
The government facing a budget deficit doesn't mean BART would be worse off with more subsidies.