Why is the healer class basically a one spell dps class?

[Roeshel]

There will always be a relative shortage of tanks and healers. These are team-focused support roles. People pick these roles so that they can have an impact.

You don't need incentives to get people to play DPS. There's just less hassle, and you can play it like it's a single player game. The problem is that because the majority of the playerbase plays DPS, that's where the majority of the focus and effort goes. You want to have impact? Play DPS. You want to have first dibs on gear upgrades? Play DPS. You want job variety? Play DPS.

You're not really giving up that much control over how the fight pans out, either. Bosses move and position themselves, so tanks don't really tank anything. Outgoing damage completely scripted, so your healers aren't reacting and making critical saves so much as they are following a set of timestamps. Anything interesting in gameplay just comes down to dps, and as we've seen in the past two expansions, there's a widening gulf between 'support' roles and the main stars of the show. Why wouldn't you play DPS? It seems obvious, in retrospect.

I play DPS. I enjoy it but I avoid playing as dps because of long queues. Not to mention, dps players have no say in how much the tank should pull, if both the healer and tanks want to do baby pulls they can only leave, while if I am a healer I can pressure the tank into doing his job.

[Lyth]

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No. The fact that there is always fewer players willing to play tank or healer than are needed in an MMO is essentially a tautology. People don't go out of their way to prove the obvious. Any official census numbers that we've gotten to date support the fact that we're not at the desired 1:1:2 ratio, which is what translates into your queue times. And that's going to be true even when you're encouraging players to pick those roles.

People will play what they find most personally rewarding. DPS is the lowest commitment role. Find 3-7 other players, jump in, and play your single player game. It will always be high value in terms of reward vs. effort. Healing and tanking can be extremely rewarding, both from a skill and community perspective, but the dev team has to give value to the odd player who goes looking for that sort of supportive playstyle with their game design.

...

It's amusing that the greatest variability in tank/healer performance comes out in dungeons. Even this seems to be more standardized than ever, given that they won't even let you pull more than two sets before you hit a wall. I daresay you could contribute just as much if not more on DPS by simply being able to burn things down faster than the average player. If not, you could always run a tank for your roulettes and then main whatever you like for content that matters.

[Kabooa]

No. The fact that there is always fewer players willing to play tank or healer than are needed in an MMO is essentially a tautology.

Then you'd have absolutely no issue just posting a few sources to back up your claim. An updated Lucky Bancho perhaps? Been a while since I had some numbers to crawl through.