Here are some details about the hardware.
This is an image of the semi-stripped mainboard. You can see that the WIFI Card is removable. Some other points of interest: The DisplayPort connector is on something that looks really like an M.2 M-Key slot. There's a buzzer.
What sorcery is this?? Apparently this is an M.2 to Thunderbolt 3 card. It appears to be using an M.2 M-Key connector.
Whether it's electrically M.2 is unknown but I have some doubts. The connector must be providing the DP signal somehow. In fact, on the mainboard, the DP connector is on a similar daughterboard connected via M.2 M-key.
If this is a standard M.2 PCIe x4 card, this would potentially give rise to adding Thunderbolt support to almost any mini-PC with M.2 availability. Truly black magic...
This is the daughterboard for the two SATA devices. Removing it requires voiding the warranty sticker.