I finally played Mass Effect 3, I'd played 1 and 2 but after all the stink about 3 and it being on Origin / EA Play for years I never bothered until a recent $1 sale on a month of that EA subscription, which has ME3 on it.

I spent 90%+ of the game going "Wow this isn't bad at all, I am really impressed! This really is a good game!"

...until I got to the ending sequence, when it felt like the game had taken crazy pills all of a sudden. I understood why everyone was mad about it, and totally agree that it ruined the game. It wasn't that Shepherd died, it wasn't the Red/Blue(/Green) choice they gave you, it was a combination of 3 factors though:

1. Crippling your character and making you limp along, unable to use any of your powers, forced to slog through a bunch of token combat EDIT with only pistol, and all your cosmetic choices were erased as you drag around at half speed through corridors just to get further in the chain of conversations.

2. Except for the pass/fail check on the conversation with the Illusive Man (which is very easy to miss the requirements for without expecting it), none of what you did before entering that final sequence matters, it really was just press a button to receive ending. On that same note, you can have all 3 endings regardless of what you did, spent the entire trilogy making nothing but Renegade choices? Don't worry you can still press the Blue button! Hail Mary deathbed confession!

3. I found the child avatar kind of out of place and a bit weird, yes I know it was a reference to the kid that died, but it was not really immersive and it made this gigantic long conversation that makes up "the last boss" really awkward, especially since half the conversation is just explaining the story for people that weren't paying attention or missed all the side quests.