It was Jerry Nixon, speaking at a Microsoft conference on behalf of MSFT as a Microsoft employee, not on person opinion. He said that Windows 10 was the last numbered version of windows directly.
Gartner did some faff around it and editoralised that into it being the last version of windows. Subtle difference.
What part of my comment falls under the "no"? It was one guy (a Microsoft employee) stating one time at one conference speaking to a completely unrelated topic (Live Tiles). You think Jerry Nixon, a developer evangelist, was the kind of person authorized to make such a statement of "Windows 10 will be the last version of Windows" while giving a presentation on Live Tiles?
If a developer evangelist was giving a talk about bringing Clippy back to Word and how you can add your own prompts and they made the statement of "we're discontinuing Xbox", would you take that as an official statement of Microsoft's intentions?
So it was a Microsoft employee speaking in a conference being quoted by the press?
There's 300,000 employees at Microsoft. You think they're all on the same page of everything all the time? This employee wasn't there to speak about the future of Windows, just to showcase how to use the new functionality of Live Tiles. It wasn't some big meeting about the future of Windows by any measure.
A statement by an official employee has been made, it was widely publicized and never corrected. The onus to correct a false statement by an employee is on the company. With the amount of publicity, Microsoft definitely knew about this false advertisement, but did not want to correct it, because it was in Microsoft's interest for public to believe it was the official truth.