I don't know what polite circles would be, but I suppose some sort of aristocracy? Certainly gentile society in 1780s in France were not scared of expressing heavy political discourse in public. Nor were the rich Romans.
Edit: And just to be clear. Rich people may perhaps only speak politics with their closest friends, but they certainly act politically with the use of their capital. Imitating them by shutting up has no point and is detrimental to a democratic society.
In America there is a tension between Jacksonian public man populism of the type you allude to and gentrified politesse of southern planters and northern merchants. In short, you’re both right.
https://en.wikipedia.org/wiki/Dreyfus_affair#/media/File:Car...
Twitter is a broadcast platform, is that so hard to realize?
Just delete your Twitter account and say nothing to anyone about anything, especially in the workplace.