The term is wide and sometimes misinterpreted, but actually not meaningless, since tankies are mainly associated with marxism-leninism (maybe sometimes maoism) and whitewashing of regimes as China, USSR, or North Korea. Same as the term "woke", which is even wider and horribly overused. Thus, I wouldn't call a western postmarxist leftist a tankie, and a lib or neocon probably would call this person a woke one :)