To me, the problem with the ending is that Mass Effect has always been a game series about consequences for your choices.
Whatever ending you get shows you almost nothing about what happens based on your final choice, and so it feels pointless. The game ends the exact same way whether you choose A B or C.
I understand Jade Empire had something like this, except you were given a text description of what happens. You don't even get that in ME3. Just explosions into a scene that doesn't really make sense and is really pretty trivial in the grand scheme of the setting into credits into an advertisement for DLC.
That last part is literal btw. The very last thing you experience before you go back to the main menu in ME3 is a promotion for future downloadable content.
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SuperNiceDog buried everyone else's hopes of winning the Guru contest in the backyard.