OWC customer help line tries to be helpful. They say this particular SSD works on macOS13 and not later versions.
This particular drive is the 4.0TB OWC Envoy Pro FX - A Thunderbolt3 portable SSD drive.
Note that I am asking about the 4TB size. Smaller sizes are shown as compatible with macOS 14 and 15.
So, their newest version of this fast Portable SSD does not work on newer OS's??? I don't believe it.
Just to be sure, I was asking if anyone has demonstrated that this particular drive works with macOS14 or 15.
This not just any SSD. It is a bus-powered portable, a fast T3 interface, and 4TB; a rare combination. And expensive, so I am being extra careful before ordering. It is very fast, but, to answer your inquiry, not nearly as fast as the 40Gbps of the T3 data port. OWC claims a real working I/O speed of 2983MBps. I only know of one external that is as fast, the OWC Thunderblade.
Thanx for the comments and photos. May I ask why you use an SSD for TimeMachine when a much cheaper 4TB rotating disk would work as well for about $100? (although the initial TimeMachine archive could take many hours. Ask me how I know!)