tl;dr
You can try to justify why JA is playing with the 3s while Mayfield, Rosen, and even Lamar Jackson got reps with the 2s, all you want. Its not gonna change anything.
I want Allen to win the QB competition. Or at least beat out pick5petermen for the back up job. I still wanna see him play with the 1s and 2s but 3rd stringers are a lot of people that wont even be in the league next year. Its short sighted to think the 3rd stringers are comparable to the 2nd stringers, even with a spike or drop in talent at some positions their still 3rd string. JA is good dont make excuses for him tho, hes good enough to not need it.