I'm still using the i3 NUC I bought about 10 years ago for one of my home theatre boxes. It started kicking off a lot of fan noise after a few years the fix was to replace the (now dry and cracked) thermal paste and the fan went back to inaudible rpms.

I have about 10 nucs in various roles around the house and the first thing I do when buying them used from ebay is replace the thermal paste and they've all been fine.