"Tankie" is absolutely an anti-communist pejorative, it's used for the same people that have been called "reds," "pinkos," "commies," etc. It's levied at supporters of existing socialist systems, which includes the likes of W.E.B. Dubois, Nelson Mandela, Fanon, Malcolm X, etc.
As for saying all states are authoritarian, I did prove it. Do you disagree with the notion that all states are elements of class oppression, and that whichever class controls the state oppresses the rest? That's the standard Marxist position, which since you're not a Marxist it's understandable that you wouldn't, but it would be best for you to be honest about your anti-communism.
i suspect you will say they exist to the extent that they are not a threat to the capitalists, but will be crushed if they were to actually gain power.
I actually agree with this, yes.
then i’d say you’d still need to prove that also, but first, how about getting a populace to actually vote for your views and win elections before crying foul.
Why would Marxists try to accomplish something proven to never work in theory nor in practice? The principles of Marxism are to unite unity and practice, learn from the past and apply it to the present. Why would we not learn from the failures of electoral socialism learned by the coup against Salvador Allende in Chile? Why would we not learn from the success of revolutionaries?
I'm worse than you feared because I'm what I've said I was the entire time? A Marxist-Leninist? How is this not an admission of anti-communism?