You state that Goff had a somewhat subpar year. Could it be that they don't feel that his normal "par", whatever that is, is good enough? He's been on a downward slide for over 2 years now.
Maybe they see what he has been over the last 41 games as who he really is. Possible?
As to competition, I've never understood why QBs have to be protected from that. They're supposed to be leaders who are the best and the strongest, not mentally fragile. If all the rest of the players are subject to competition and they handle it well, why shouldn't the QB have to compete too and be expected to handle it well?
My guess is the other players in the room don't mind the QB being subject to the same competition they have to go through.