I own a bunch of them, generations five through ten, and have always had a love/hate relationship with them. None has ever died on me. My main workstation at home, as well as two “homelab” servers are NUCs. They Just Work<tm> under both Ubuntu and Proxmox.

The love is for them just working. The hate is for Intel :-)

What they got wrong:

• cooling. CPU cooling is finely tuned and controllable through the BIOS, no qualms there. The disk and the NVME SSD have no cooling whatsoever. Sticking an small 40mm fan to the side and running it at the minimum RPM drops the case temperature from 60°C to 40°C and avoids the NVME SSD burning out. Needless to say, a glued on fan looks fugly.
• opening. By refusing to let their firmware be accessible to the fwupdmgr mechanism, Intel forces its Linux users to physically go to the machine, stick in a USB thumbdrive, keyboard and a monitor, and click their way through the BIOS update. In contrast, my Dell gear gets updated online through fwupdmgr, and I just have to suffer a reboot with a few minutes of downtime. I don’t even have to be at the keyboard.
• remote monitoring. I bought two NUC’s with vPRO support, to allow for remote management. But the remote console sucks eggs even from a Windows management station, so I wound up disabling it on all of them. Both Dell’s iDRAC and HP’s ILO run circles around vPRO based remote management.

That’s not a lot to go wrong for such a big endeavour, which is why I will keep hating Intel and sorely missing the upgrade opportunity. Just hoping Dell will step into the void.

What do you recommend for desktops that aren’t the big ass tower?

Really depends on what you are using it for

• Internet browsing and media consumption on a big monitor? Light code development and/or office work? Just get a semi-modern laptop with USB c (preferably thunderbolt) out and a hub.
• Gaming: Honestly? The Steam Deck or one of the other vita form factor PCs are surprisingly good bang for your buck gaming wise. Same rules regarding a hub and monitors. And some gaming laptops are pretty affordable too.
• “Power user”: Build an htpc/mini-itx build and learn to hate everything about cable management

I love my big ass full sized tower. But the vast majority of computer users would be fine with a laptop and a dock/hub.

I think user asked for a small factor PC, just like intel nuc. IMO intel nuc is a perfect PC for a work desktop. They can even mount on the back of the monitor - excellent feature. Not sure if any other brand has such feature.

People ask for a lot of things. But it boils down to what they are actually trying to do.

The nuc was… a bad product. Power wise, the moment you do anything you start running into thermal issues. Getting a used one cheap is great for home automation and lightweight server work. But in terms of actual user computing? A laptop is better in almost every possible way. If only because you aren’t mounting it to the back of a monitor: it IS the monitor.

In a lot of ways, nucs felt like a pretty big misstep even at the time. We already had thin(nish) clients in the form of the Solaris Sun ray and the like. Which, to a corporate environment, provides pretty much all the benefits AND a much more centralized security model (we see a shift back to that with the push for VDI solutions).

And from the conversation with that user: They want a computer for gaming. A nuc was never going to be that. A low-ish tier gaming laptop (I have a Razer Blade Stealth that I love) might do that. But they have their heart set on a “real computer”. MAYBE a nuc-like with a good APU could do that but… thermals. Which means, a desktop of some form. Whether it is an HTPC or a tower or whatever.