Did I specify P/S was a good DPS for PvE specifically? I did not.
And yes, druids are unconventional and weird healers, but I never said they were bad at what they do. I suppose I could call them quirky but that's an understatement in my opinion. Priest just provides a better flat heal without any added HOTs. Need I meantion Soul Source? And as far as I can tell, druids don't get a cleanse skill, they get an anti-poison but I haven't seen any curse removers. My big concern which makes me rate druids lower than priests (even if they had 2x better heals) is the fact that they don't get a self-rez like the priest's Soul Bond.
So in short, they're great healers, just a little wonky in their methods. They seem to be less party support and more self defence, note the 99% damage reduction skill, various debuffs and the many HOTs they get to out heal most damage.
not inferior healers, just quirky.
Your "P/S can be considered a DPS class" is misleading if you're meaning strictly PvP, since you didn't specify.
Anyway, as for druids~
D/S - Group Exorcism is an AoE cleanse that works on most things the single-target priest Cleanse will. In addition to that, they can remove certain debuffs that priests can't. Has two AoE HoTs that can be kept on the party at all times.
D/W - Has an extra AoE heal, giving it two instant burst heals, and the
best physical buff in the game -- far better than Amp Attack. It also has Nourish.
D/M - Extra AoE HoT, single-target HP buff, party-wide matk/healing 30s buff, and with the 70 elite can reduce a heal's cast time to less than a second.
D/Wd - Mdam buff, Briar Shield, Soul Source that is better than a priest's.
All druids have both a curse remover and a poison remover. Druid single-target heals can far out-burst UH, they're just longer cast times, which is why druids have HoTs/other insant heals as well. The HoTs druids possess (D/S in particular) add up to a pretty large amount of heals per second, and that's not something to scoff at. While your priest is charging their GH, the D/W is using back-to-back instant burst GHs, the D/S is soaking up the damage with their HoTs, and the D/Wd is insta-full-healing the party every minute.
Sure, priest is simple. You spam just a few heals. The fact that druids have many, many skills to juggle doesn't make them "quirky," it just makes them more intense to play. A bad druid will likely be much worse at keeping a party alive than a bad priest. A good druid can perform very, very well for healing, and the debuffs can be very useful if utilized correctly. The class isn't straightforward. There are a lot of skills to manage, everything from HoTs to burst heal to AoE heals to debuffs to cleanses, all while managing your Nature's Power. You can't sleep through an instance on a druid.
The lack of Soul Bond is a non-issue for most things. How someone can consider druids only "defensive" instead of "support" is beyond me, unless you've never seen a good druid heal before.