How would an optional, official parser be toxic?

[Ryaz]

There are toxic people in the community, I'm afraid, and I don't think SE wants to really allocate the resources to deal with another source of it. For example, I was in Suzaku Ex the other day and had ONE bad fight because I was a bit distracted. Despite the fact that I cleared her three times just before that with no issues, the healer started to rag on me like I was a noob who had no clue what I was doing (and ignored others who also died, some to the simplest mechanics). Some people are just jerks.

An official parser would be fine IF it was just for you to use as a means to improve yourself. Many would just use it as another tool to exclude people. Not that it matters much anyway because SE can't really stop people from using third party parsers.