There are of course family and lifestyle considerations, that's why I stayed when I could have left.

TPIC is a commodity. CKA is great if you know its in the cards.

But if the regionals start failing operationally due to pilot shortage, the legacies will slow or stop hiring their own feed pilots. They would then logically hire their competitors pilots instead. If you're at an LCC you then have choices, rather than being chained to regional oar.