for having including a link that itself contained links to websites youtube associates with nsfw content

If that is true, and if they were linking to NSFW content, then those bans are consistent with policies that youtube had had (and have made clear) for a very long time.

Most of the time when I hear stories about "youtube unfairly banned my channel for no reason" it was people who had been intentionally breaking youtube's rules and were upset that they got busted.

I'm not trying to defend youtube here, but I have little sympathy for people who FAFO then whine about getting caught.