Like, I remember as recently as 2016, that term was just used as a mocking term for weird larpers. Now, it's used as a term for people they want to purge from the left (yes, I'm using those words. How they're acting is literally the definition of purging, it doesn't have to include violence).
Now that the libs are starting to pick up "tankie" I fully believe shortly after it becomes a common word for them the reactionaries in the more fringe regions of their media culture will start using it unironically against the libs, and by the time we see the bowtie dipshit on Fox calling Pelosi a tankie for eating ice cream or something stupid the shitibs will turn around and go "yaaas we're tankies!" And coopt tankie much like how they co-opted antifa, blm, che's face, etc.
"Tankie" will mean "liberal hawk" in about 2 years. The tank is because they love our big beautiful US Army tanks!