Re: The Next Mass Effect & Commander Shepard
I agree with @SofaJockeyUK.
There is a lot that points to a timeline that is on the level of Andromeda, so 600+ years after ME3.
This gives the devs plenty of opportune to find a reason why the effects of the endings, no matter what they player choosed, are just not visible anymore.
Canonised the ending would mean to have another shit storm on hand before the game even is finished.