First, I apologize, I haven't been a subscriber to this reddit, so if this is similar to previous discussions, sorry.

So let's go through ending by ending

Red: obviously the "bad" ending, but it makes sense from the standpoint of having done the minimal amount of effort to "save" the galaxy. You destroy the reapers, but the associated costs, morally, are very high. I'll provide a bit more comment on this in the next endings as well.

Green: Red Herring ending In what I'm starting to suspect is one of the best twists in a game, this seemingly optimal ending is in fact, merely the easiest choice, but not the best choice. So you've gone through the game and brought as much force to bear against the reapers as possible, and you're presented with this new "middle way" solution that allows everyone to get along. But it's like demanding that instead of resolving the differences between species we shoehorn them together into some unified framework. We remove the differences between these separate factions rather than finding a way to make them work.

Blue ending: Morally optimal ending. So the red ending imprecisely uses the crucible to destroy all synthetic life. But clearly while the Reapers are malevolent and belicose, EDI and the geth are at worst no worse than any other organic species. Even the geth were just fighting for their survival and let the organics be once that survival was secured. Probably better than some organic species like the Krogan or Rachni, right? Now perhaps an even more optimal ending would be to use the threat of the crucible to broker peace between the Reapers and the rest of life, much like the various Atom bomb allusions throughout the storyline. But given these choices, a morally good person in control of the Reapers should be able to stop the war and preserve the several kinds of life. Here too there was a red herring in seeing the Illusive man seek these ends. The Illusive man is simply the wrong choice for a leader of the Reapers. Shep (presuming you care about morality to begin with) should be able to lead the Reapers into peaceful coexistence. Now note, I'm on my second playthrough, so there may be some subtlety to the blue ending solution that I'm forgetting, but this is going to be my choice.

Also, the other major problem I have is the destruction of the Mass Effect Relay system. That's just bad news for everyone, no? But if you think about it, with the Blue and Green endings, keeping the very technologically advanced Reapers, the galaxy might be able to rebuild after the war; the relays being a kind of collateral damage again akin to an Atom Bomb. And again the red ending serves well if we assume it's the right ending for not bringing enough support.

So my thoughts are that the ending wasn't bad it's just that it actually required sitting down and thinking of all the consequences of your choice. Something I think is actually a fantastic move for the game!

Edit: Sorry I really absolutely don't mean to imply that players were too "stupid" to get what they were going for, I'm merely trying to provide an alternative argument that I think is reasonably well thought out to justify the endings as they are. There are still some poor design choices, and it's not an optimal end, but I think that what remains is simply more information, rather than junking the endings as they are and trying to somehow redo it. Explain what happens after our choices. Fill in some plot hole gaps. But the choices themselves are reasonable.