It was less the tendency for liberals to be drawn towards ubermensch sentimentality and more the material conditions the Western tanks were created under. The Soviet T-64/72/80 series would end up with about ~43.5k produced. The production run for Western tanks are around ~16k total. Add in the vast amount of T-55s/62s and various BMPs and that would create some pressure on them to somehow cope with fighting the Soviet and Warsaw Pact where being outnumbered 3:1 is to be expected.

Combined with the fact that Western procurement has to factor in the profit motive for armaments production and having missed out on the weight-saving technological solutions of autoloaders and ERA at the time, Western tank development would inevitably be drawn to weight busting, costly tanks.