I don't understand how you can say it's meaningless.
It's easy once you read it or when you're not too occupied preaching.
I never understood the mass effect hate in this regard either.
It's been stated what's the issue concerning ME3 plenty of times. Also, not sure when I used the word "hate".
For me, in a RPG...simply having the choice makes all the difference for me.
I, on the other hand, would like to believe that the decisions I make in the game are final and that they are NOT out of my reach, namely by having the choice I made being overridden in a rather arbitrary fashion, which is the case here.
My character letting someone live...only for them to be killed by someone else later...is vastly different than my character killing that person....in my opinion.
And like I said, the choice is meaningless from the moment whatever you choose is overridden arbitrary, without even being addressed as to the "WHY" the latter decision was taken.