This is simply the Sopranos ending over again....the people who get it, like it. the people who don't, complain and then blame the writers instead of themselves. All throughout the final season of the Sopranos, clues are given to what happens at the end, and smart people figure it out, that Tony Soprano got whacked or that his life will always be of danger. It was an ending, not a cliffhanger, and it was so genre, but done in a refreshing way.
Really, the ending, while not perfect, works, for those who actually think, but not overthink like many on this board keep doing. Its thematically complex but structurally straightforward. The Catalyst was indeed defeated by Shepard, before you meet him. But instead of having a moronic boss fight, it is beaten intellectually, so he talks to you and reveals himself. So right before Anderson dies, you win. And you win not only in the present but any future cycles, which the writers did incredible job taken that into account. But the Catalyst is not the authority people who criticize the ending think he is. He never was....he is just another flawed well intentioned extremist which causes him to be an antagonist. Nothing more. But about making a tough choice...that's its theme, just because you don't like it doesn't mean its flawed. Hell, in a way, the ending literally fits the title MASS EFFECT. Its not Guardians of the Galaxy, its MASS EFFECT. To have your choices use MASS EEFECT tech to have a MASS EFFECT on the galaxy works.
And really, those who try to use the word "Art" as a bad thing just want to dumb things down.
Well The Witcher 3 is "art", and oh, its great. no dumbing down of anything, unlike say DAI which narratively, is dumbed down from DA2 while not really learning why DA2's story was flawed (it was rushed KOTOR 2 style). And DAI is certainly dumbed down from ME3. DAI is a game that wanted to please everybody, so no risks were taken, and in the end, DAI was so toothless. CD Projeckt RED understands that you do not have to please everybody or dumb things down to have success. Bioware should learn this, and those that whine about something because they don't understand or like it, and not judge by the works own merits but judge by what they want from it, need to shut up and either pay more attention to the story or learn that just because you don't like it doesn't mean its flawed.