Well, wouldn't it kind of defeat the purpose of a complete twist ending if a character said "Oh hey, Shep...maybe you're indoctrinated??" The subtle hints are precisely why it would be so damn brilliant if it ended up being true.
Also, I never once said "paid" DLC. I said DLC. I have stated numerous times that I think it would be totally bogus if a proposed "true ending" DLC cost anything. If it wasn't free, it would be even worse. So, yeah.
Also, you're kind of being hypocritical, because you're essentially saying the indoctrination would piss off a huge majority of players so Bioware shouldn't do it, but meanwhile there's an equal majority just as pissed with the ending Bioware already gave. So, what to do, then? Can't please everyone, right? So perhaps the best solution (if indoctrination is true) would be to release the "true ending" DLC for free and if you want to accept your default ending as default, simply don't download the DLC. Problem solved for everyone!!!!