There is nothing wrong with current Intel NUC's hardware. HDR support has just appeared in Linux kernel 5.3 and it is not yet implemented in Kodi.
The Milhouse Matrix (Kodi 19) LE alpha builds with Linux 5.3 have just started. I’ve ordered a new NVME SSD especially for testing these builds on my NUC8i3BEH. I’ll leave my current LE 9.2 SSD untouched so I have a fully working Kodi 18.4.