No one in my real life would consider me anything other than kind, giving, and rational. I share things with them I wouldn’t say online. Even Kyburz admits to self censoring. That doesn’t mean I’m an extremist or even wrong. To some I’m a nazi, which is absurd. To others I’m a filthy pinko commie, which is equally absurd.
I don't feel the same way. I avoid a few topics that people probably would call me an extremist for opinions about, but they're rarely topics of conversation anyway. The internet is full of people from all ends of all spectra, so inevitably everyone will be called either a literal Hitler or a literal Stalin given enough time on the web. That doesn't make either of those extremes correct, nor even worth considering. They're both absurd, as you say, but that doesn't reflect poorly on you, but rather on the people making the claim.