You have highlighted one of the flaws of proportional representation. This system does give legitimacy to extreme views.

I was in Slovakia in 1994. One the parties thought the Slovak Army should march to Budapest for some kind of small war with Hungary. Enough Slovaks still voted for this party to give it representation in parliament. And with that representation, that party got more public attention than it deserved.

Having said, the moderating effects of first-past-the-post systems are being lost.

It is time for a new way of democracy.