I'm here to say that the Gutenberg team is going to take a step back and rewrite Gutenberg using a different library. It will likely delay Gutenberg at least a few weeks, and may push the release into next year.
Automattic will also use whatever we choose for Gutenberg to rewrite Calypso — that will take a lot longer, and Automattic still has no issue with the patents clause, but the long-term consistency with core is worth more than a short-term hit to Automattic’s business from a rewrite.
This is a big blow to React. The framework will still be massively popular and adopted but the number of developers in a thriving ecosystem like Automattic's products - like WordPress - that now have to move onto something else is a big blow. Automattic's continued use of React would have meant thousands of jobs for a long number of years.
As usual, Mullenweg sees the longterm angle, and weighs that against the core principles upon which his company was founded, and I believe he's taking the right path.