3. DJ Moore is the straw that stirs the drink on offense
This one could be controversial because the team does have three legitimate wide receivers. Could they survive a week or two without Moore? Perhaps, but he is ascending to one of the best receivers in the game, and the other receivers fit around him more than the other way around.
Keenan Allen is aging and will mostly stick in the slot, where he can sit underneath and move the chains. Rome Odunze will ascend into an irreplaceable receiver, but he is a rookie right now. A lot of his game will be taking the top off.
These players in their defined roles will allow Moore to be the true number-one wide out in this offense. Without Moore, there would be a lot more attention on Odunze and Allen and while they would not get completely erased, both would have to ascend above the roles they are expected to play this season.
One of the other cases for Moore, or any of these receivers is that the depth gets very thin beyond the big three. Tyler Scott has shown little to trust him stepping into one of those roles, and they have DeAndre Carter and Velus Jones beyond that. Both are on the roster to be kick returners.
Moore is the top receiver and if they lost him, the team would feel it.