I'm avoiding AIBU because threads there often end in an argument and I really don't want one.
So, if I don't get "traffic" I'll accept it.
There are various, what may be described as, "Isms". It seems to me.
For example, often people who criticise Meghan Markle or Prince Harry are accused of racism.
(I mention that because, personally, I've noticed it quite a bit.)
But ageism seems to me the most prevalent and least objected to on MN.
Just throwing that out there for a (hopefully reasonable and well argued) debate.