Spot on. This game demonstrates the problem more elegantly than any essay ever could (Nick has some *amazing* other “games” just like this one on other topics):
an interactive guide to the game theory of why & how we trust each otherncase.me
It uses game theory to demonstrate how 100% trust (or in this case, tolerance) eventually leads to the destruction of trust. Instead, the optimal strategy turns out to be: Trust initially and freely, and if someone messes up, give them the benefit of the doubt once or twice, and after that, assume they are intentionally breaking the contract.
The game demonstrates how this results in a stable strategy that survives within populations over long periods of time. The interesting part is that it requires participants to actively police the process (thus the benefit of the doubt only once or twice. This is akin to what you mention: Being intolerant of intolerance, because allowing it to creep in poisons the conversation.
The responsibility, then, lay with us in what we consider intolerant. So much of our own bias and emotional reaction plays into that.