shinsuke's only 36 so could last years, although who knows if he'll stay there that whole time. joe is the type that can work into his 40's, he's 37 now. he'll be fine too.
aries + roode i haven't seen much of, and they're both closer to 40, so yeah on them. they both look great though, look in their prime.
NXT's main event region is heavy with 35+ guys right now.
see the issue is they are bring these guys in who are IN their prime, and then holding off on them. but maybe that's the plan, maybe it's to keep NXT seeming important. NXT would be looking utterly bereft of names right now with them - so sure, keep these guys hanging around, propping it up, and build the next stars in the meantime.