But you shouldn’t have a say in how anything is decided. You shouldn’t have the right to vote,

There's a certain irony here as one of the early things the Nazis did was make other parties illegal so as to ensure they would remain in power despite a hypothetically democratic process. Depending on how you define "Nazi" (what is the bare minimum position or action one would have to have/take to count as a "Nazi"?), this touches awfully close to that.

Your second point is the exact point that I addressed. There is no “paving the way”. They will do it if they want to, regardless of what we do now.

No, that's not what I was saying. The "someone else" I was referring to wasn't the Nazis or any other extremist group; it was some other person, likely later on in history, probably well-meaning and certainly part of the mainstream, using our decision to strip Nazis of their rights as precedent for stripping another group of those same rights. People like, say, rapists. Rapists are bad, right? Why do they deserve rights? Or how about just anyone who expresses a bigoted belief? People who are convicted of crimes? I hope you see the point: it's the slippery slope argument. You open the door just a crack, because you think in this particular instance it's justified, and soon someone else comes along and says, "hey, here's another instance I think is justified;" faster than you'd think, the door is wide open and our government itself has become the fascist terror organization.

My point is more addressed at civil rights. Civil rights are taken away all the time. You lose your right in the USA to vote, to own firearms if convicted of a felony.

Civil rights are different and not what I was objecting to in the original comment.

Basic human rights must be guaranteed. That's what separates us from them. But beyond that? I completely agree, fuck them. Nazis should not have free speech, because Nazis sure as hell won't give you free speech.

It needs to follow a paradox of tolerance situation -- if someone would use X right to get into power so they can take away X from people on the basis of race, religion, sex, orientation, identity, ethnicity, etc then they relinquish X right.

On the surface this seems hypocritical, but it really isn't. Stripping white supremacists and Nazis of free speech is not taking away a right on the basis of race, religion, sex, orientation, identity, nor ethnicity. It's taking it away on the basis that they think a born trait makes someone inherently inferior to them. Believing in discrimination is not a born trait. Plus, there's also the order. The express purpose of limiting the right is to protect vulnerable groups from losing it.