It doesn't take up that much space. Here's a Raspberry Pi sized board with an M.2 slot: https://www.cnx-software.com/wp-content/uploads/2018/11/RK33...

I think there'd easily be room, given that the soldered-on NAND chips could be removed from the board.

edit: If you're wondering how that works, here's a hint: https://raw.githubusercontent.com/ThomasKaiser/Knowledge/mas...