>But I recall eventually thinking that if the mantra of communist revolution was a forceful overthrow of existing government -- by definition not the will of the (majority) people - then a ban on the parties (public) existence was justified. Do you agree with the premise and if so does it affect the equality of your comparison at all (the free speech restrictions)?

Depends. Is your country trying to restrict even democratic socialists, respectful of human rights, from operating openly? Does your country use infiltration and assassination to grind its Left into dust? If so, you may just have to deal with the tankie communists.