The whole problem with the whole "writers who don't have dicks for heads will be forced to change their endings for the dickheads" is the fact that, you know...
NOT EVERYONE BUT ARTISTS ARE DICKHEADS.
There are tons of very intelligent people out there who just don't write books, or paint pictures, or design games, or whatever. But that doesn't automatically mean that somehow their views on those subjects are invalid.
See, this gets into tricky territory, because a large number of people out there ARE dickheads, I mean, lets be honest here. But we shouldn't let the silliness of some (or even most) people automatically invalidate those that have legitimate ideas or complaints.
And a number of the complaints about the Mass Effect ending are legitimate, intelligent, carefully researched, etc.
Again, as I have stated in previous posts, calling an artists work "sacred" and "totally their own" is extremely silly. I can't even begin to go into all the problems involved with that... Aiiieee tcha. Someone's work is never truly their own, and you know what? THAT IS AWESOME. Not a tragedy. Sorry guys. Figure it out for yourselves.
If someone does something poorly I think it is perfectly fine for an audience to call them out on their bullshit. If the chance is presented to correct said bullshit, than an artist should listen to the intelligent people and consider the option.
If they decide not to, whatever, that's their choice. But if they decide to change it that's hardly a bad thing. More a good thing really.