I'm stupid in this space, but as an outsider, is this "the end of an era" because it looks like MapBox is simply pulling the tried and true "bait and switch" which has been around forever.

In that regard, "open core" (or open source for that matter) was never a business model — the business model always was bait and switch. Open was the bait.

But likely I have always been a little suspicious of "open source" and likely I am now over-simplifying.