It’ll be even grander when I don’t have to fear for my son’s life because of a variant whose growth and spread was spurred by ignoramuses who reinforce each other’s ignorance.

Reddit is private message board run by a for-profit business. It's no more "the public square" than Fox News is.

There have been many startups lately that are explicitly allowing this type of content, and the users of that subreddit are free to migrate there.

The no new normal folk are free to build their own platform and govern it as they like. Reddit is making a business decision not a moral one. These people are creating too much heat.

Will be?

It's been the case since time immemorial.

Has there ever been a time where that wasn't the case? Maybe for a very brief period during the past ten years due to social media.