Melicamp wrote...
The only pertinent knowledge for understanding the ending must be contained within the main narrative for the trilogy to be considered a properly constructed story. In this case even the information within the codex and side quests should be considered extra flavour due to the ability to skip them, because otherwise it means there will be players who may arrive at the end without all the necessary facts to comprehend it. If that were the case (I think not) then BioWare have failed at a basic storytelling principal. Even if the explanation were contained in outside material that is no excuse for an ending that does not stay in keeping with the story arc's internal logic.
Like Star Wars without episodes 1-3?
And I've mostly only seen claims like "OMG this is so NOT the ending I WANTED" in counter arguments like yours. The majority of complainants are dissatisfied by the fact the ending goes aganst many core thematic elements of the series and makes little sense in itself, not because they didn't get exactly what they wanted. If the same events unfolded but were told in a way that was actually comprehensible, with Shepard acting consistently, then most of us wouldn't be here.
They do make sense like I said if people would actually read more on the backstories .. not difficult

Like how Shepard was rebuilt by reaper tech which the Illusive Man has (as in has in his body)