Warlocks and Boomkins are not nearly as reliant on their passive dmg reduction as shadow priests are. Not only do they have much more defensive cds, they also have much better mobility.
And the physical damage reduction will barely matter at all because every physical damage class has other types of damage and it's still a 3% reduction even.
You may be right about locks with gate/portal, but you are off about moonkin. You have the ability to go invis, we have blink. That's basically it. If you think travel form counts then you haven't played a druid recently. By going in travel form you lose the dmg reduction from moonkin and there are so many passive slows constantly reapplied in the game currently that it's become less and less often you even bother going into travel form. This was actually one of the main issues I talked about with Moonkin becoming stronger in a recent blog: our mobility used to be a strength and now that there are a million and one gap closers it's really nothing special anymore. Body and Soul or Angelic Feather are equally as strong, if not more so, than travel form in it's current form.
In fact, moonkin doesn't even have the instant peels that priests have with fear (unless you spec roar, which breaks on dot damage unlike fear) so you could say that's less mobility because it doesn't allow us to 'get away'. I'm not trying to say we have less mobility than you, but it isn't anything special.
Also, what makes you think we have more defensives with melee on you than priests?
-might of ursoc
-baseline instant cc (fear/disarm/silence - ours is casted)
Fairly equal IMHO - we can spec into more that changes gameplay obviously (blink, roar, typhoon, fearbot, angelic bulwark/invis, etc) but overall there isn't some clear advantage that Moonkin have over spriests. This change hurts us as much as you.