It was an anonymous letter with a lot of generalizations.
Which means it’s not remotely actionable since anyone could say anything.
It also means that whoever wrote it clearly didn’t want a rebuttal. It’s like sending a mad message on facebook and blocking the other person so they can’t respond. It’s a cheap shot with no context.
I’m really not going to be mindful of anything that’s said by someone who makes those kinds of general statements while also shirking all accountability for their words.