The doubt is to their survivability on the battlefield against a peer opponent - look at the Russian SU-25 loss rate and multiply in several fold.
In the Fulda Gap scenario it was expected they would all die in 1-2 days, as was expected of Harriers etc…
But times move on and EO pods, UAVs and SATCOM together with both air and ground launched extended range PGMs (whether Air, truck, ATACMS or artillery launched) enable effects based instant targeting from a safe range - there is no need to put a multi-million pound platform and pilot at risk.
The only role left for the A-10 is COIN in a benign environment - and there are cheaper airframe options, repeatedly explored.