In my experience, it’s most important to give them a path to leave their position without losing face.
Many times, it may look like someone is arguing in bad faith, even though they’re really just wrong about something or may even just have a different perspective on things.
If you approach them by saying “Hey, this is a common misconception, here’s why it’s wrong.” or “Hey, my experience is like this, is yours different?”, then they can easily come back around and learn from you, or teach you something.
If you’re assuming they’re arguing in bad faith, chances are, they think the same of you, so breaking that up before you try to bring in your best arguments, is in the interest of everyone involved.
For the rare cases that someone is genuinely arguing in bad faith (i.e. trolling, really), I find it most effective to make it clear that you’re not personally invested in them not being an asshole. If they want to be intolerant, so be it.
But that does not mean that you tolerate their intolerance. If they’re intolerant, they break with the social contract of tolerance and will be treated as lesser.
That way, you:
nix the fun of trolling you.
make it clear that they’re being dumb.
give them a clear path out of there (i.e. simply not being an asshole).