I can't find it again but I read a few days ago a slightly different variant of this story, maybe before the layoffs, in which Zuck/Chan were reported to be summoning CZI executives and asking them what they are actually doing all day and what their projects are. From the quotes in the report it sounded like the foundation was very lightly managed by them, and they suddenly noticed that it was full of projects that were actually maybe useless. Apparently the layoffs indicate they didn't see a way to cancel all those projects whilst staying on good enough terms with the people running them, which makes sense.