We've been talking about it in the chatroom since yesterday.
I think it's legit, yes, by which I mean that this obscure media outlet did get access to Akira Shimada through the
current collaboration with Uniqlo on a couple of t-shirts. I'd be curious to know what the exact conditions were, though (written questions sent through Uniqlo?). Would have to ask this Joe Goodwin fellow who wrote it.
Anyway, people seem to be getting excessively agitated over what amounts to very little as far as I can tell. It's plain to see this interview was poorly prepared, poorly edited and poorly translated as well. Its title is misleading, its questions are badly worded and there are moments where you can tell they didn't understand what Shimada was saying. More importantly, it doesn't really say anything new. Shimada gives good, sensible answers like you'd expect from an executive of his stature, mostly repeating already available information or handing out careful statements.
I think this applies to his last answer as well, the one about the ending (which seems to be all people care about). They have him say:
"All I can tell you about it is that it’s not a happy ending nor is it a bad ending. Nothing you can put into a mold we’ve grown accustomed to, but it’s truly a tremendous ending."
To be clear, if there's one thing Shimada isn't going to reveal, it's the ending. The whole Continuation hinges on that. So his point here is that it's great and doesn't fall into an easily definable category. A pretty boilerplate answer that is just a way to not give a real response. And I wouldn't be surprised if his actual answer in Japanese was even more noncommittal than it comes across in this version.
So long story short, I wouldn't read too much into it.