I never even said the word protocol, so not sure what you are on about. I did slightly misspeak and incorrectly used form factor. However, M.2 SATA drives do infact exist as well as M.2 NVMe drives. When most people say M.2 then mean an M.2 NVMe drive, and many seem to think, as you do, that those are the only M.2 drives that exist. You are wrong. M.2 is the form factor, SATA or NVMe are the interface.