This makes about as much sense as being intolerant to intolerance.
You’re free to privately believe that privacy shouldn’t exist. That is materially different from trying to eradicate privacy to cement state control over a populace — in an age where the State has almost immeasurably great power to track, monitor, and police its citizens.
While I don't consider the paradox of tolerance to be invalid, what I see happening is people using Popper as an excuse to be intolerant towards people they dislike, declaring that their target party is "intolerant" so they're allowed to be - or even have to be - intolerant towards them. Hence, the total amount of intolerance in the world increases either way. It seems like quite a damned if you do, damned if you don't situation.
I guess it depends on what you mean by being intolerant. Preventing them from being violent or telling them that their views are wrong is one thing. Rejecting people for expressing their views is another. Both Neo-Nazis and ISIS recruit from those who feel as outsiders for whatever reason. Making them outcasts for having been recruited just serves to radicalize people further, locks them into their echo chambers and prevents them from rebounding into normal society.
I don't know. I can't even say if society stagnating is bad. I think society improved over the centuries and millennia, but of course I agree that the values I was raised into are the right ones. I don't have objective measures to verify this. I think I have good reasons and could argue them for hours, but in the end it's no different than arguing religion. The best chain of reasoning is worthless if the axioms are chosen arbitrarily.