https://quillette.com/2019/02/17/a-witch-hunt-on-instagram/
https://quillette.com/2019/06/07/instagrams-diversity-wars-r...
https://quillette.com/2019/07/28/knittings-infinity-war-part...
You could gather and directly examine evidence yourself:
https://fringeassociation.com/2019/01/07/2019-my-year-of-col...
https://fringeassociation.com/2019/01/07/2019-my-year-of-col...
Ultimately I guess you have to make your own judgement of what kind of ideas and behaviour you deem 'reasonable'. The difficulty, I suppose, is if you yourself are caught up in one of these purity spiralling communities. It's hard to maintain objectivity in such a situation. Delusional people don't know that they're delusional. People caught up in a cult don't think they're in a cult.
I've seen people only come to understand how insane things are when the mob finally turns on them, but by then it's too late to get out unscathed.