Most likely a proprietary connection. Not your standard NVMe.
Definitely a proprietary connector, and not even the same as in the current MacPro. Also the module is very short, so it's not practical to have adapters for standard M.2 drives; a M.2 2230 may fit, possibly a 2242 but certainly not a 2280. Who'd like a small capacity DRAM-less M.2 2230 SSD, as typically found in cheap laptops, in his Mac Studio?
OWC may make suitable modules, but they will likely cost 150-200% the price of standard SSDs of the same capacity so it's still best to get the right amount of first-tier storage from Apple—and put the rest on Thunderbolt or in a NAS with 10G networking.
I want to see the video where they try to reassemble it. That would be entertaining.
I second that! Spending $17k on three Mac Studio (that's a lot of T-shirts to sell!), moving immediately from unboxing an Ultra to dismounting it without ever powering it up… All of that ungrounded, on a nice but not anti-static wooden table, and spreading the parts around in no obviously apparent order. Hmmm, let's hope he trains his memory as well as he trains his upper body in the gym.
So we know the Studio can be taken apart—tediously—, that ports can be replaced if damaged (good!), that storage could be upgraded (even though it would still be easiest to have it done by an Apple "Genius", at Apple price) or moved from one damaged Mac Studio to its replacement, and that there's an Apple logo well hidden where the sun never shines and no-one is
ever supposed to look.
Still, better avoid dust in the first place!