We still need to take bets on when the first real mainstream use of the word "tankie" happens and in what context. Will Trump or one of his surrogates decry Biden as a tankie? Will some lamestream media person CNN say it on primetime about either real communists, liberals, or even the more reactionary elements? Perhaps some blithering liberal tool will call Trump one. Or perhaps some zionist shill will accuse all of the pro-palestine marchers of being tankies. In fact the last one seems slightly more probable to my mind though it'll likely occur on a more reactionary network like Fox because CNN and such like to pretend there are no marches or support for Palestine while Fox has an interest in hyping the idea of domestic Hamas because their audience is incredibly naive and credulous and will believe they're coming over the southern border.
My gut feeling tells me the first real-life usage of tankie will be some handwringing liberal dork on CNN trying to blame Biden's loss on scary online left-wing extremists.