Sure they are.
Eagles are more consistent with Hurt then Mariota. Though Mariota moves well, he is not the running option Hurt brings. Eagles actually fall a bit if Hurt can't go.
Ravens identity is Jackson, he gets hurt,
Tyler Huntley will not be able to continue what Jackson can do at QB. Ravens would suffer even bigger loss then Eagles.
Cowboys have shown lately to be more of a run at you team, with great Defense, but Prescott is the reason their not one dementional, he goes down, bringing in Trey Lance, the Cowboys would be very one dementional, and much easier to defend.
Finally 49ers are a very well coached team, but what Purdy has been doing has been unreal, and if you think
Darnold can replicate it, you will find out how wrong you are.
No matter what, it's a passing league, so even running teams need a passing game to get their running game to work, and very few Backup can do for their team what the starters can...especially good teams.