That I hadn't seen but it is unsurprising. My interest has been in adding eGPU to relatively low-end boards with the current crop of M.2 to OCuLink boards, which is an inexpensive way to get better performance than Thunderbolt if you can find an unoccupied M.2 with sufficient connected lanes (and can work within tradeoffs like no hot-swap).
https://pcisig.com/pci-express%C2%AE-oculink-specification-r...