The completely speculative answer makes extremely valid points, I don't have much to add about that, besides: yes, it looks like SE Inc. is "re-focusing" on its "core business" to increase ROI for their investors.
Yet, this is tagged discussion, so let me add this:
When reading the website, there seems to be little to no information regarding this function.
I think that is the really essential core of everything. Sure, there also seems to a bit of incompetence around and politically motivated over-welcoming-issues. But in the end, it might be all about a company trying to find strategies that lead to long-term business success. There are people who put in their money to get this company going, and some day, these people want to see results. A business needs to make profit, or it is doomed.
And honestly: I think that is okay. Everything changes, and old promises don't get employees their paycheck. But the essential element here: transparency!
Assume SE Inc. had just stated something like this:
We think we can't get to robust roadmap while upholding "promises" given 5 or 10 years ago. We think we need to ramp up on the stackoverflow side of things, and reduce efforts for all the smaller communities. We know this will be painful to many, but we are willing to sit down with the communities to find solutions that work for all of us. ...
in 2019. Sure, we would have wept, and screamed, but hey: there would have been a chance to work on that together.
I think: you can even make such announcements in a way that convinces external business people, analysts, and shareholders. Whereas the "communication strategy" that SE Inc. decided for has a high potential of achieving the exact opposite. I would hope that any decent analyst figured by now that SE Inc. managed to drive away the expert-content-providers in masses.