Could Shepard survive all endings?

Its giving the player another choice. The ending doesn't change. Just Shepard ends up surviving.

Shepard does survive Control - by ascending to a higher level of existence. Shepard does survive Synthesis - by becoming diffused throughout all life in the galaxy (well, that's how I interpreted it). Who is to say that finite, mortal life culminating in inevitable death is a better option than either of these?

Themikefest's idea of EDI controlling the Reapers might have made Control more palatable, to me.

But yes, Shepard's survival is not the only problem.  Not even the biggest one, really.  Though at the same time, it is a problem

Shepard sacrificing themselves to save the galaxy was never a problem for me. What freaked me out was seeing Joker's weird green eyes and then all the other races. To be honest my first ever play through, which was before they brought out the additional content, I was frankly befuddled by the whole exposition by the AI kid, which back then was pretty sparse on the details. Then suddenly I was faced with a decision and the colour coding didn't help my confusion. Why was destroy red and thus considered the renegade/ruthless choice? Hadn't I fought my way through 3 games to reach the point when I could remove these dreadful beings from the galaxy altogether, even at the cost of my own life? Why would effectively joining with them, even if I was in control, be the paragon choice? It wasn't about losing my life but that I seemed to recall I had just shot TIM for suggesting doing that. It just seem the wrong choice for a hero to make, becoming supreme overlord of the galaxy. If they hadn't coloured it red, I'd have gone right but the colour made me think that there was something bad about that decision and of course I remembered how I hadn't wanted the Geth to have the Reaper Code but that was presented as the ideal choice too and the only way for them to survive.

So I remembered the mind share I'd had with Liara only a short while back and the bright white light, which is how the path straight ahead looked, so I took it thinking that had been a clue. Then Shepard disintegrated and all the green weirdness followed and my reaction was that I'd been taken in by the AI and this was the ending if you'd succumbed to indoctrination at the very end. Surely this is what the damned Reaper lord had wanted all along? So I went back, re-did the final bit and went with red, thoroughly annoyed how the writers had painted me into a corner with forcing the Reaper Code on the Geth so they would be destroyed along with the Reapers and Shepard but at least the galaxy would finally be free. I did not agree with the notion that everything would ultimately go the same way with history repeating itself but quite frankly, even if it did, that was for future generations to take responsibility for. I had achieved what I set out to do.

Now the later additions seemed to indicated that Shepard does survive if your EMS is high enough (without playing multi-player as was the case before) but that wasn't the reason I felt Destroy was the only genuinely heroic ending and a fitting finale to the series.

Hot take
Shepard get survived, because the cybernetic implants that were used to bring him back from the dead, kept working, post-mortem and brought him back regardless.

Well looking at the recent trailer it would seem that is the case. There are dead reapers shown on the planet and a wrecked Citadel/Relay (could be either). Now it would be possible to accommodate Control with this as possibly Shepard overlord eventually chose to implode or some other form of AI suicide but not Synthesis, so it seems like they decided to dispense with the dodgy 3 choice ending and opt for a simple Destroy one.

I did wonder if that might be part of the reason Casey Hudson decided to leave. After all, that whole mess was his idea but may be he still stood by it.