I don't think I'm morally bound to evade taxes for the same reason I'm not morally bound to stop the world's massive amounts of animal suffering. My utility function breaks if I take my morality too seriously. As you say, I am somewhat bound morally to try and evade taxes or even actively stage insurrection against my government. Both of those seem like very bad ideas, as the state will just crush me.

Not working for the government in lieu of trying to bring down the government is similar to my decision to eat less meet rather than trying to make the whole world eat less meat. Yes, I am aware that these are not anywhere close to perfectly analogous decisions.