You don’t. If you’re even entertaining the thought that there is more to learn than what you already know you are displaying intelligence. Stupid people “know” they’re NOT stupid and intelligent people constantly question their own intelligence. This is why a grown adult with the reading age of a 12yr old can spend twenty minutes online and become the world’s foremost authority on… 5G, vaccines, international geo politics, chemtrails, why the Nazi party were “ackshully” socialist etc. etc.
What I’m saying is that whilst actual Tankies did, and still do, exist you do not have to be one to be called one. It’s now become a catch-all slur applied well outside of its original target.