Pretty much this:

Quote Originally Posted by Colorful View Post
We don't need a nice step towards a group parser, we need a group parser for EX primals and content above that level. A group parser will of course measure your own DPS, so you could use that for your improving your skills too.
The issue is that so many players take this:

Quote Originally Posted by Rawrz View Post
wants to use parsers to directly judge the contributions of others in order to adjust performance or replace if needed and to see where the group struggles the most during phases.
As a form of a personal attack, or are unable to deal with constructive criticism.

If there is a case of legitimate player harassment, the GMs are there to deal with that. However overall player transparency is never a bad thing.