It gives certain customers time to mitigate - and certain others time to exploit - the issue before the embargo is lifted. It maintains the customer/vendor relationship. It also allows Intel, even if current products are still impacted, a head start on R&D for future products before disclosure. Remember Intel also has their own Linux, has their own compiler suite, and directly supports development of Linux and Windows (and probably macOS for Apple) for their industry partners. So they could have been working on figuring out software mitigations during that time which they can now share.

Revolving door? Or even just someone looking to retire or otherwise cash out son who didn’t want the stock price to drop yet?