Published 2014.
Published today.
Sure. It certainly isn't ruled out.
The multiplayer quote from the article published today is from a meeting back in March. The OP has an interview from July where Sean goes back to saying it's possible but rare. Not sure if you're trying to illustrate a timeline about Sean's change is design of the multiplayer, but that doesn't hold any weight.
He has also never mentioned the word "instancing" when discussing the multiplayer aspect, which is something that we're left to scrounge and piece together ourselves. That burden really shouldn't be on us.
The fact is, his "explanations" have been very vague, but I get that development changes probably had him worried about sticking to a story. But if the feature was completely removed, he should have come out and said that.
But for now that too is speculation, and we have to wait for his official comment on the matter (likely) tomorrow. If this is about occupying the same instance, it will be annoying to consider the fact that he never explicitly stated that. If this is a server issue, then we're all gravy. (But considering how long its taking him to make a statement, it's at best the former)