While possible, with a high precision clock it should be quite rare. In any case, UUID's aren't meant to be universally unique to the point you will never see the same one for any reason across every use case in the galaxy, although many versions do allow you to neglect to code to handle collisions for almost every practical use case.
If you need 16 million entries to get a 50% chance of collision, 100ns time resolution means you have 10^7 timestamps per second, so to actually experience a 50% chance of collision requires an instantaneous hash rate of over 10^14 per second, which I don't think you are likely to ever see in practice before these UUID versions are long obsolete.
If you need 16 million entries to get a 50% chance of collision, 100ns time resolution means you have 10^7 timestamps per second, so to actually experience a 50% chance of collision requires an instantaneous hash rate of over 10^14 per second, which I don't think you are likely to ever see in practice before these UUID versions are long obsolete.