It was my impression the NUC sold by Intel was always meant to be a proof of concept for the NUC-class device to inspire third parties to make them. Intel getting out of the market now that it's proven sort of makes sense.
None of these players are interested in budget systems either, which is where my attraction to NUC platform was, Celeron. None of the big players touch Celeron, they only make I3, I5, and I7 systems, all in excess of $600 ea.
I can get a Celeron intel NUC fully equipment with a Windows Lic for less than 1/2 that that is perfectly suited for Line of Business Applications, Kiosk Machines, or other Low I/O, Low Memory single Application workloads.
Things that could run on PI or other ARM SBC if not for the application stack requirement of Win32 API and the management integration of Windows (Active Directory, Intune, ConfigMgr) etc.
I see alot of comments on here about how Great the NUC linux compatibility is. Ironically the Main Reason I use Intel NUC platform in a commercial setting is because of its Windows Compatibility, something alot of the low cost, tiny form factor, SBC platforms (like Odriod, rPI, etc) lack. I require Windows for my environment unfortunately .
Losing this outlet for them is a loss for Intel to bring new considerations to their platform beyond just chips. Again, if Intel was looking at NUC as a profit center, surely it was smart to shut it down. But I highly doubt the NUC line was a significant revenue generator to begin with. Because that wasn't the real value add for Intel. It got people talking about Intel and using it. That is one of the greatest forms of marketing for a chip manufacturer.