*snip* "Blue baby squadron" *snip*
The reason I dislike IT is mostly because it is essentially "it was all a dream", it craps on your choices, steals player agency, and leaves you with no real meaning for your actions, much like the original ending. More on this below.
"only your actions will be remembered" (Samara) - Hmm, could this mean something? Could everything/almost everything 'matter', but in a different context? 
Or maybe nothing matters and we get a 100% clean slate. Maybe we'll learn at E3. *shrug*
What does "a different context" means? That the Reapers will hold a memorial day for the amusing insect called "The Shepard"?
The original ME3 ending felt like it stripped any meaning from your choices, after the game itself hijacked player agency by forcing
those boring chores of nightmares about a boy that shouldn't have had a big emotional impact considering the bigger picture,
especially on a renegade Shepard.
Now consider IT, is this any better when it comes to player agency, choices and consequences? I don't think so.
All you did was inside a virtual reality, while the Reapers sucked you dry of your life. Essentially the last illusions of a feverish mind.
That is what I mean by a freck you ending.
If you could somehow "escape the Metrix" and continue the story, that would be quite different, but as a final ending? Just no.
By the way, I would have liked seeing a logical ending similar to the ME4 leak:
"Everyone did what they could, but obviously the Reapers are still winning despite some losses here and there.In a final bid for survival a secret armada of live-ships, exploration, security and support space craft is assembled. Defeating the reapers head on might not have been possible, but retreating to another galaxy or to deep space until the Reapers return to dark space,will give us the time to start anew, and perhaps in time, find allies and technologies powerful enough to rid our home galaxy of the Reaper's monstrous shadow." In this situation you still lose, but there are no ludicrous starbrats, no unlikely "forgotten weapons", no surrender to a a fate worse than death (forced transformation into the very monster you fought, without any kind of free will.), and yet there is some hope for a future, and for the elimination of the Reaper threat.