I think this has more to do with wanting to see McKinstry or whatever other LHH IF they cycle through. If you look at his numbers, Schoop has almost zero career OPS platoon split. Cut it a little finer it is still a muddled picture. He had a big platoon split in 21 - you might expect it to get bigger for your average player as they pass by their prime, but the ironic thing is that last year he collapsed against LHP even worse than RHP, putting up a reverse platoon split of 80 points. So no immediate reason to think he's going to be all that much better against LHP. But you would expect the LHH like McKinstry to have the bigger split to protect as most LHH do.
As noted above, the Harris regime does not seem disposed to give Schoop any legacy priority - he's going to have to play his way back into a regular job if he can.