Yes moonkins are gear depended, by a lot. There is no way you can make that many mistakes to have 150k less dps then me on a same fight and still able to kill the boss. As I said, i think your crit is a bit low, but that doesnt have to be an issue. I had 15k+ 2 weeks ago and now i'm on <12K but my dps is better since i gain more then 2k intellect .
Now sure how much of a dps meta brings but dont be surprised to see that its more then a legendary back. On Malkorok normal it was only some 3.5% dmg done.
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Tanks are new dps. On some fight with insane vengeance, they can do much much more then a dps class.
Also moonkins are hybrid class so dont expect to top the meters if you have pure dps class there