There seems to be significant opportunity to zig as others zag. Imagine the Intel letter saying "we are going to take advantage of the current hiring environment to scoop up talent, and push forward on initiatives."
I thought about this a lot over the years.
I saw something that piqued my interest last year though, and kind've helped connect the dots. I was on a cruise, and most of the ship was available to guests. One day, one room was cordoned off to an invite-only meeting. The windows weren't blocked, but on the screen was a presentation about AI investments, number of jobs saved (reduced), and etc.
I found one of the attendants later during the voyage and chatted her up. She was head of HR in some big company, and the meeting was supposed to be private. But it contained a lot more than just spreadsheets about AI investments. There was homework and whatnot, but the attendees weren't all from a single company. It was "direction setting". I don't think it was Intel (topic under discussion) but certainly some loosely related tech industry.
I'm convinced that it was nothing less than business collusion.
So, back to your question:
> why do all these business leaders all do the same things at the same time?
Because they're told to.