Unless Dallas were to fall to say 3-4 and this losing streak goes out past a couple of games then things could change. Garrett has been in place since 2010, but most fans know he is in place because the Owner and FO have his ear, not all coaches currently on the 31 other NFL Teams could handle it in Dallas.
Adam Gase is not for long at the rate things are going. They are looking like a 2-4 win team at best and some of that has to fall on his shoulders. If for some reason Miami decides it's OK to beat this team and succeeds which I don't believe they really can but if they upset the Jets, Gase might not make it past Thanksgiving...if Darnold looks terrible it might even be Trick or Treat, lights out for Gase.
Kitchens is under a lot of heat, as Cleveland drifts back to at best a wildcard team in the coming weeks...they get Pitt twice, Miami, there's a path even after they lose to New England where they could be 6-6 or better going into December, that's usually a "Still in the mix" bunch.
Teams I can't see any head coaching changes...NewEng, Buff, Balt, Pitt(Tomlin is fine), Cinci(New guy), South looks OK for now, West?
I don't see a ton of movement in the 2020 off season. A lot of QBs taken in last 1-2 years and those coaches are going to be given a chance to develop them at least another season or two.