The problem is that of all the guided weapons cold war Su-25s used, NONE of them had any antitank capability, absolutely all of the were designed either for anti radar, command bunker destruction or logistics bombing while the mavericks had excellentb antitank capability whicvh would allow A10s to do standoff strikes against warsaw pact armored assaults, with the Su-25 it
was COMPLETELY impossivble to engage AFVs without having to fly into SAM range in order to attack NATO vehicles.
Su-25 was not a strike aircraft, nor was it anti tank... think of it more in terms of being a Stuka rather than a Shturmovik.
... and a 250kg bomb will destroy any armoured vehicle with a direct hit BTW.
If a Soviet unit was attacking a well defended position and had SAMs defending it the Su-17/22s or Mig-27s would likely use Kh-25MP missiles with a standoff range of 40km or so. Su-25s would be armed with rockets and bombs but for anti armour roles they would take anti armour submunitions bombs with top attack explosively formed fragments munitions to wipe out large numbers of tanks rapidly.
In other words, in a NATO-warsaw pact conflict, Su-25s, unlike their ancestor, the Il-2, would've only been useful for tactical strikes against static targets and maybe suppression and destruction of soft targets and infantry, and unlike the A10, would be ALMOST USELESS against NATO armored formations with legitimate SAM and AAA defence(gepards, mistrals, stingers, rolands, vulcan, ADATS, etc.)
Unlike? Gepards, Mistrals, Stingers, Rolands, Vulcan, ADATS... Gepards are very few in number... only the West Germans used those, Mistrals and Stingers are only MANPADS, Roland is a useful system, Vulcan was rubbish, and ADATS was not very widely deployed at all.
In comparison the A-10 has to fight through Igla, Tunguska-M, TOR, OSA, Shilka, SA-9, SA-13, and SA-11/17... and in rather greater numbers than NATO deploys their air defence systems.
Both aircraft are COIN aircraft and neither would have lasted very long in WWIII.