“Tankies” don’t exist.
People who unironically use the word “tankie” would say it’s someone who uncritically supports communist governments, but if you ever look at someone using it, it’s always because they are uncritically against all communist governments and so they interpret nuance or historical understanding as blind loyalty to communism.
People should vote to gauge strength, show solidarity with their movement and demonstrate how to those unaware that the system isn’t working and therefore requires replacing it with one that will.