It's sad that so much hard work is being deleted, but it's par for the course for the entertainment industry. If someone is deemed radioactive by the entertainment industry because they're guilty of truly heinous shit, the stuff they were in will get removed from circulation. We've all seen it happen before, this is just the latest example.
But doesn't this raise all sorts of hard questions for JP fans. Imagine being a Japanese Nijisanji fan and while you could pretty much ignore the shitshow from the EN branch, this latest mishap has you asking really hard questions you really don't want to think about, like, "did this happen to one of my oshis?", "why didn't Nijisanji put in enough safeguards to prevent this from happening to the talents while they were working for Nijisanji?" and "how much did Nijisanji know before the news broke?" Those aren't questions I want to be thinking about while watching any sort of entertainment, and certainly not when I'm deciding whether to open my wallet to support a talent and the company they work for.