I cannot ever support any kind of in-game parser, or even official support for external ones.

Most people who want these tools want them for self-improvement and as a positive way to enhance performance. However "most" isn't "all" and there enough people that love using these as way to bully and inflate egos to constitute a problem. Even though the jerks are probably outnumbered 3:1, they're 10 times as loud and eager to prove it.

The harm the bad actors will cause is of a far greater magnitude than the good it will do. Certainly not having parser isn't causing all the jerks out there to suddenly be great guys, but it is depriving them of a powerful tool.