I'm a little surprised we don't see small battery backup systems built into PCs or available as an add-on. One thing I really like about laptops is that they essentially come with a built-in UPS, and I would love (some of) the desktops I work with to have that functionality built-in as well.

Somebody please correct me if this thing exists and is available, I'd love to be wrong!

Managed 500 physical machines over the course of 20 years, no UPS, never had a problem where power loss caused data corruption or loss.

Lucky you. I have not been that lucky. Heck, I had one go up in flames even though it had a surge protector because of an up-down-up-down event. F'n video card.