It is a double-edged sword.

On the one side we have those who use parsers, be it against the ToS or not (It is, for now.). When they do, they point it out to the player with the low dps which leads to rejection of the player with the lower dps.

The REAL problem is that the developer, in this case being Square Enix, do not allow parsers so that players can improve and figure out why their damage was low. - To practice, in other words.
Now, because using a parser IS against the terms of service, I take it most players follow the terms of service, like myself. However, the developer must realize that what they are doing is to create a wall of rejection, separating people with lower dps, and hinder them from doing content that requires higher numbered dps. - Sure, the Echo is a thing, but should we really be needing that? No.

They should release an official parser so that players do not have to worry about 3:rd party malware and other malicious stuff. It would let us learn from our mistakes, and it would create cracks in the wall of rejection, eventually, in best case, break a lot of it down.