I mean staff can certainly adjust to a new genre. They'll also probably hire a lot of new staff. They've already hired some new staff (I think I heard something of Halo 5 and Naughty Dog devs, but I could be wrong). Either way, i'm mostly worried about if we'll get any Retro game in the near future. I hope their unknown project wasn't cancelled.
For sure, I just mean you cant assume Retro will do great since they did 3 already because it's not the same people.
And yes they have hired alot of people who had experience with other big games. If I recall they got some people from the studios you mentioned and I also think people who worked on stuff like Darksiders, Crysis and Bioshock but I might be remembering wrong as well.
I really hope the rumored Star Fox game by them is real and releasing this year, it would be a real shame if they have nothing released between Tropical Freeze and Prime 4, that will be like 7-8 years between releases for them.
When the herd loses its way, the shepard must kill the bull that leads them astray.