Just in general, even making mild suggestions about anything having to do with how people play is met with either complete silence or people losing their minds.

Couple of days ago I did Qitana Ravel and had to Tank as SAM because the Tank was a booster and was just randomly using his cds on cd and only random single target attacks on one mob at a time ( he still double pulled ).
At the start he was talking and everything so he was clearly not a mute, and neither were the others I think they knew each other.

After a couple of pulls I said '' so I am SAM tanking? '' and the Healer responds with lol.
Couple of more pulls and somehow managing first boss I said '' Tank can you use some AoE please? I am getting the aggro ''.
Complete silence and he continued doing the same thing, I was Tanking the whole way through and no one listened to me on last boss and we actually ran out of time, first time that has ever happened for me.
They actually did talk too at last boss Tank included and were just spaming wtf and such when they died to every mechanic.
I marked myself and everything and explained the mechanics but nope, nothing got through to them.

Some people are just hopeless, no matter how hard you try they can't even manage something as simple as pushing their AoE button.
Even just the one button would've been better than what this Tank was doing but nah couldn't even do that even when pointed out to him.

I've had people lose their minds and get mad at me too for telling a SAM to not stand in front of the boss in Nier Raids.
The SAM even responded to me and said thanks, I think he had boosted too and was new didn't know what was going on, but after everyone lost their minds at me the SAM thought I was in the wrong and went back to standing in front of the boss and died constantly to cleaves.

This stuff is just one of the most baffling and annoying thing about the FFXIV community to me.
I still think FFXIV has the best community, but this is just one of the quirks that I truly don't understand.
Everyone acts as if literally any comment on how someone is playing is the same as being toxic, it's not.