@FORBIN Taiwan is more likely to be on the defensive, in the event of ground combat operations the main threat would likely be an amphibious assault. As such heavy MBTs would likely be "late to the party".
Abrams has done Okay in a number of terrain types but the weight is an issue. As Taiwan is an island and it's geostrategic position is such that it's armed forces are a Defence force in a literal sense. As such they need there mainline tank to be able to traverse the length and breadth of the landmass. A lighter tracked armored vehicle could do that more easily then the Abrams or Leopard 2.
@plawolf the Taiwanese aren't very likely to get those PRC light tanks, now are they? And if those light tanks arrived on Taiwan they wouldn't be turned over to Taiwanese crews...
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optimally the Taiwanese would need something like the Japanese type 10 tank but at the moment seems not possible. Although the Japanese have opened up export options for there indigenous technologies, they seem to be targeting aviation and some degree of maritime, and even then they seem to pick and choose under strong protective provisions.
The M60A3 is still the mainline MBT of a number of nations and there are a number of comprehensive upgrade programs. Increasing both armor, fire power, hourse power and technology to a near match of modern machines. Including regunning up to a 120mm main gun. It's just a question of getting the technology. Which I am sure a nearby power will do everything conceivable to prevent.