Welcome.My 2021 Acadia AT4 has the same problem with the peeling grill. Dealer cannot cover it under warranty, and my 7/150,000 ESP doesn't cover it either. 23,670 miles on the vehicle, paid extra for the trim level upgrade, only to have my vehicle look terrible!
I called GMC to ask about coverage for inferior paint/coating and was denied. When I asked to speak with a Manager, that request was also denied.
Disappointing to say the least.