4K Blu-ray discs have some extra encryption or something and most PC disc drives do not work with it. This forum post seems to be the go-to community resource for identifying the specific models which actually are capable of ripping 4K Blu-ray discs: https://forum.makemkv.com/forum/viewtopic.php?t=19634 But standard Blu-ray and DVD can be ripped with pretty much any drive. Go nuts.