Why couldn't they be? Crap, I hope CKM put some energy and focus on those 2 to see what we really have because truth is, we don't know. We look at height, arm talent, and lack of success in a funked up situation but I believe we still have more to see from both of them.
I'm going to be very honest with you; in this modern age of football, I haven't seen one QB that elevates the roster. The top guys have weapons (Burrow) and if they have a down season, they will say that they need weapons (Mahomes). When you look at a QB making those around them better, I can't think of one, and if we are being honest, we have more examples now of skill players elevating QBs as opposed to QBs elevating the players. The franchise is usually an entire team effort.
I agree with the nuance of the term and that's why I don't like to use it. What determines is someone is franchise QB quality. People bashed Brock Purdy because they look at him as being a "system QB," (all successful QBs are BTW), "game manager," etc, even though he took the 49ers to the playoffs and was a play or 2 away from winning (Chris Jones....the real MVP..lol). But we Matt Stafford, who has never won a playoff game in Detroit, go to a ready made team that went to the Super Bowl an few year prior, and for some reason, we view those 2 situations differently (yes, I know the Rams won but you get my point..haha)