I am guessing you already know this, given all the information that you have posted, but "caliber parity" alone would not be sufficient to penetrate an Abrams/T

I am guessing you already know this, given all the information that you have posted, but "caliber parity" alone would not be sufficient to penetrate an Abrams/T-90/Chally/whatever. Today's 120mm rounds are kinetic-penetrator sabot rounds* (link below if someone really wants the details and naming conventions). The point is that this round is way longer than WWII tank rounds and functions completely differently. None of the tanks you listed would penetrate a modern tank from the front (100%), I would guess they are unlikely to penetrate from any aspect, but I am not ready to provide data proving that. Note that even T-72s are currently being updated specifically to be able to use LONGER rounds, and every developed country has chosen to BYPASS 150+mm cannons in favor of using longer 12x rounds. We can also get fancy and talk about active protection systems (APS), which would defend against slow WWII rounds as well as they protect against RPGs since the 90s. Though, no one but Israel has really fielded APS in serious numbers since the USSR pioneered the concept. * https://en.wikipedia.org/wiki/Armour-piercing_fin-stabilized_discarding_sabot https://en.wikipedia.org/wiki/Armour-piercing_fin-stabilized...