As I said... it's the design of combat that results in DPS getting a slide usually, NOT the lack of an official parser. Think about it? What happens when you throw in MORE people to a situation (e.g. CT raids)? Your individual presence is no longer as important. In smaller content, let's say 4-man content. There is only 1 healer to keep people alive, and 1 tank to keep people alive. They have more responsibility to the party than DPS do in order to prevent death.
What if 4-man parties comprised of 1 DPS, 2 heals, and 1 tank? Lets also just assume healers can't DPS for some mysterious reason (magic!!). Who's gonna stand out there? The tank? Sure. Only 1 like normal, afterall. The healer? Probably not since that'd be WAY too much potential healing with current content. The DPS? Most definitely... that ONE DPS is on spotlight to get the target down reasonably quick. It's rarely okay to ridicule others, regardless of role. Just like the more popular people (e.g. celebrities) stand out IRL, and thus they'll have haters, so too do the roles that stand out the most. You will be judged and criticized because we, as human beings, are pitiful when it comes to that.
With the holy trinity design, it literally puts the spotlight and significant responsibility upon the tanks and healers. The DPS, in most MMORPGs with this format, are run of the mill expectations. Nothing critical about them. That is BY DESIGN with that format. This is a significant reason why people steer away from the roles. They have A LOT of responsibility that DPS do not... again, by design. Why do you think people rarely pay attention to DPS in regards to commendation handouts usually going to heals/tanks? There's a reason for that, just so you know.
The fact you actually think that that reason is a cop-out, SCREAMS that you're ignoring everything logical to push an irrelevant want (i.e. parsers in this topic). The witch hunt comment indeed holds true with what you've stated so far, but I want to specifically point out that it's now also in regards to what you will do with official parsers. Outside of raids like Coil, I don't think there's really a necessity for a parser to exist. It's not like it's impossible to do typical DF instances outside of it, afterall.