This is a beautiful essay. I might only make a couple of comments:
(1) Unfortunately, the term "Open Society" has been co-opted by the adversaries of open societies. It is sort of Orwellian, really.
(2) Karl Popper's work in the 40s included 2 massive volumes, examining the question of "tolerance". One of Popper's main conclusions was that if a society is tolerant of intolerance, it will not survive very long.
And again, in another Orwellian twist, the progressives/wokeists/critical justice warriors and their fellow travelers cloak their demands in the sheep's clothing of "tolerance". This is "weaponized compassion", as some have dubbed it. Of course, there is nothing "tolerant" or "fair" or "diverse" or "inclusive" or "kind" or "just" about what the woke push for. But as long as they call it tolerant, fair, diverse, inclusive, kind, just, etc., it is enough to fool a fairly substantial fraction of the population, a good portion of the time. And at least over the short term, this subterfuge can carry the day, at least temporarily.
Are these ironically self-described "anti-racists" and "anti-fascists" now sufficiently revealed and unmasked that their power and leverage and influence is starting to diminish? One can only hope.