Yes, they are called microSD Express Cards and you can buy them today everywhere.
t-3 175 days ago [-]
Those are similar but different. These are meant for more permanent installation, not to be removed and replaced often or hotswapped, and IO speeds should be significantly higher. This is more of an attempt to replace M.2 with a smaller-footprint slot, not add a new type of hotswappable storage.
Rendered at 07:40:11 GMT+0000 (Coordinated Universal Time) with Vercel.
The size is nothing new, but the packaging into some sort of slottable physical interface with good signal integrity is somewhat new.
That makes something like this likely adaptable to thunderbolt with a dumb passive adapter.