This, this right here - and it's not just the US where this shows up (although it's definitely the most extreme). At the core, I think, it's all about "free speech": when you have a constitutional right to say whatever you want, without any limitations, you will first get a bunch of contrarians yelling all sorts of offensive stuff around "for the lulz"/"because they can", and eventually that sort of stuff gets normalized, and then societal cohesion (especially when the offensive stuff is directed towards minorities) and eventually society itself gets poisoned.
"The paradox of tolerance states that if a society is tolerant without limit, its ability to be tolerant is eventually ceased or destroyed by the intolerant. Karl Popper described it as the seemingly self-contradictory idea that in order to maintain a tolerant society, the society must retain the right to be intolerant of intolerance."
"Tolerance is not a moral absolute; it is a peace treaty. Tolerance is a social norm because it allows different people to live side-by-side without being at each other’s throats [..] the model of a peace treaty differs from the model of a moral precept in one simple way: the protection of a peace treaty only extends to those willing to abide by its terms."
- https://medium.com/extra-extra/tolerance-is-not-a-moral-prec...
At first blush, "tolerance" seems like a decent precept. You don't bug me, I don't bug you. But it takes only a moment's thought to realize that it doesn't work.
And that effectively makes it pointless. The peace treaty is routinely broken, and might as well not exist. The precept works perfectly well for the situations where it's not needed -- most of the time tolerance is also in your own immediate best interests. But as soon as you try to extend it to cover anything else, it fails.
Too bad. Back to the moral drawing board. Meantime, we can describe ourselves as "tolerant", if it makes us happy, and pretend it's the reason we're doing what we do. But it won't help us make any hard choices.