wifi driver is actually included, it's just not enabled in DT. Issue here is that board comes without wifi and thus it should not be enabled by default. Addon boards should be handled by DT overlays (something like it's done on RaspberryPi), but nobody took time to implement such mechanism yet.
Bluetooth is low priority so it's not implemented for any board. IIUC, RTL8723BS bluetooth needs some patches which are not in mainline kernel yet, but it's being worked upon. However, even if they would be included, you still have same issue as before with DT overlays.