If you are going to have DPS Checks, you are going to need to make available tool for people to diagnose and improve performance - or not stop others from doing so.
If you aren't going to have DPS Checks, you might as well remove Damage Dealer as a role - because then you just want to bring more healers or more tanks (people that can fill up hp bars, and people that are sturdy vs hits if/when they mess up mechanics)

Healers don't get a pass when they are bad.
Tanks don't get a pass when they are bad.
I shouldn't get a pass if I'm bad.

A parser is a tool. A tool in itself is not good nor evil. A hammer can either help you build a house or bash in a skull.
The hammer itself isn't toxic. So don't tell us we can't have hammers just because your super sensitive self is worried a toxic person is going to use one to hit you on the head with it - they don't need one.

SquareEnix already follows through with reports of people being abusive while using parsing tools - and as far as I am aware, they do a great job at it.
I don't see why that would change.

Leave hammers alone.