the fighter mafia basically wanted more maneuverability, cheaper planes and CAS than interdiction bombing. A-10 is all of those except light.
they were vehemently opposed to optimizing planes for beyond visual range (BVR) combat like by improving sensors or stealth because they considered it "a fantasy."
problem is missiles fired 100 miles away don't care what you consider fantastical.
the A-10 is actually a giant hunk of junk outside of COIN operations. it has no stealth, it's slow and its gun is useless against modern armor. against terrorists in flipflops with AKs it can be useful but that's only because they don't have any sort of AA. even stingers are a huge problem. and in an uncontested airspace you may as well bring in a plane with even more firepower and loiter time like an ac-130.
so basically the a-10 in this day and age is a solution in search of a problem. it's big, slow, heavy and would be shot out of the sky in a peer confrontation before you could even blink. its gun is useless against modern tanks and an f-35 can carry a similar amount of munitions.