No, it generally doesn't matter to the majors. Although if a regional has some sort of very contentious labor issue (ie alter ego operations), you should avoid that because those on the receiving end will hold a grudge for a long time and may eventually end up in a position to influence hiring. There are no such alter-ego regionals at this time, gojets was the last a number of years ago but at this point I doubt many folks would hold a grudge against a current gojets pilot.