It should be noted that the forums are a pretty poor random sampling of FF14 players. I would expect the forum population to have a much higher proportion of hardcore/elite players vs casual players compared to the actual population distribution in game(this is based of no known statistics, just my experience with MMORPGs). I would assume the elite players to be more inclined towards allowing an official parser which likely has a lot to do with the numbers we see here.

It should also be noted that many of the hardcore/elite players want a parser not because they want to know their DPS (lets be honest, they are likely already using 3rd party software) but because they want to hold other people accountable for a lack of DPS. Nothing really wrong with that except this is likely going to be directed at dps they meet in PuGs (theoretically they don't have to worry about their FC or friends reporting them for using 3rd party software). I have no issue with people getting reprimanded for sleep walking through a zone. But I don't like the idea of some inexperienced casual trying to finish his daily leveling roulette getting abused (or just randomly kicked) because he can't keep up with some ilvl synced hardcore in 230 gear.