May I say that I never actually understood the M247 Sergeant York? I mean, the US was already well underway with the M1 Abrams and the M2 Bradley, two of the most modern and best pieces of hardware at the turn of the decade into the 80s. And then they devise something so ugly, patched together and insanely ad-hoc like the M247 and cannot even make it work?
I mean, look at that
thing: The chassis of the Gepard was not new, it's based on the Leopard 1, but the M247 is based on the M48 and the turret is so boxy that it looks like a WW2 tank missing a couple of rivets.
There were good contenders, Raytheon's Dutch Gepard turret could have been mated with an M48 chassis, General Dynamics mated the 35 mm Oerlion guns used by the Gepard with CIWS systems using what looks like a M48 chassis as well. And finally General Electric wanted to use the 30 mm GAU-8 Avenger. Probably an outlier solution, unless T-72s were known to grow wings.