Originally, a “tankie” was a Stalin apologist, but in more modern times, it’s come to mean just authoritarian communist. I don’t think it’s a self-applied term. More a derisive term used by anti-authoritarian leftists.
The anti-authoritarian communists tend to call themsleves anarchists, anarcho-communists, anarcho-syndicalists, left libertarians, etc. And they’d strongly tend not to have anything good to say about Stalin, Mao, or the CCP.
(There are right-wingers who call themselves “anarchists” or “anarcho-capitalists” or “voluntarists” or “minarchists” or “Libertarians” (note the capital “L”) or whatever, but they have pretty much nothing to do with the hard-left-wing anarchist movement that they appropriated the terms “anarchist” and “libertarian” from.)
And all the communists in this thread arguing with you hate the regimes that have killed millions (including the ones that have embraced the term “communist” like the CCP and Stalin’s USSR) as much as you do.