https://www.espn.com/mlb/attendance
Have to feel sorry for the Rays...10-0 and that level of home crowd support, even if it is very vocal.
Detroit (unless the current rebuild completely flops), Minnesota, Cleveland (as long as they keep winning), KC...are all in (relatively) decent shape financially.
The teams you have to be most worried about are the A's (obviously planning to leave for Vegas), Cincy (with that ownership, although it's really a baseball town through thick and thin, like Colorado), Rays and Miami Marlins.