I'm not entirely seeing the problem here - so far there's been two arguments why parsers should not be implemented.

1. They may be abused by assholes who will name and shame you by dropping your 'X' DPS in party chat for all the world to see.

You can report them for harassment, depending obviously on how they say it. If they say something akin to "lol Neko your DPS is mcshit I was pulling that in ilvl 70 gear uninstall the game and go kill urself" then yep, sending a ticket. If they're like "Neko, you're doing less than half the DPS of the other DPS, can you please concentrate more on your rotation or look up a guide before re-attempting the fight?" then that, to me, is alright. However, it seems like the second sentence is scaring all of the DPS players on this sub-forum from having their inability being called out in any way, when Healers and Tanks get criticism (constructive or otherwise) straight off the bat. You failed to tank swap in Bismarck Ex? People will call you out on it. You can't keep up with the outgoing damage from Atma-Linga in Ravana Ex? You will get called out on it. You do sub 500 DPS up to ph 2 in Bismarck Ex? Nope can't call you out on it, because lolparsers i repot u huehuehue.

In short, report the assholes and get them suspended/banned. Because a parser is there doesn't mean that you have to act like a dick. The GMs will sort out what constitutes harassment and also decide if the reportee was just being unnecessarily butthurt. It's their job.

2. People will start randomly asking for SS of your individual parsers.

This would not be a problem with group parsers, but rather if they implement individual parsers (because no-one else would have any idea of what you're pulling except for you and those already using ACT). I have to admit I would react like someone who posted before, and instantly vote-kick a person in DF who goes around screaming for SSs of personal parsers or AFK and who starts trying to boot people unless they post their numbers up in a random DF PUG (majority rules is a wonderful thing). However, if it is in PF, I do not see why they are not entitled to post their expectation of what DPS they want the DPS in their group to bring to the table.

I don't even care if they put "need 1100+ DPS for Ramuh Pony Farm post SS." It's their PF, their rules. Don't like it? Don't join and go make your own. The people who don't like it, and refuse to make their own party that doesn't have such bleeding-edge DPS requirements are generally looking to get carried and are upset they're being excluded because they can't reach the high levels of play that these groups require of them. Note that this last opinion is only applicable to PFs, as you have the right to select who goes into your PF and who doesn't make the cut. DFs are an entirely different story, and you should approach it knowing that you get a mixed bag of people who may or may not conform to your own standards.