If you're starting flight training anytime soon or further along than that, there will be plenty of regional stepping stone opportunities for you on the road to majors. If upgrades stall, the majors will just hire regional SIC's.

Possibility that regionals might downsize to a shadow of their current size in the long run, but if that happens the majors will probably have to do ab-initio training because THEY are going to need pilots badly.

Worst case, you'll start on a narrowbody instead of an RJ.