We also migrated all the file servers into a per-team file store with no folder hierarchy (thousands of files in each team's share), because "the search capabilities are so good now, you don't need folders to organise your data anymore!".
That one was less than optimal.

There's a handful of teachers who still use it, and send weird, non-clarified, messages about my kids' performance.

I have no idea who it is, so I just ignore the emails

Unusually for Microsoft, I think this product's capabilities were slightly overstated by the marketing team....

It's a wonderful piece of software that every idiot thinks it can do more than it does... oh, I see where you're coming from

It felt to me like someone took an old version of SharePoint (maybe 2010?) and then somehow made it even worse.

They custom built their own platform in the mid 90s. And so can probably never move off it, because everything would break.

But, that also means its pre-fancy and entirely functional.

I can't escape the madness

So glad my kid's school doesn't use it.