Excellent post. There is just one point I think deserves a little more elaboration.
I think the more important disadvantage to combining GNSS with the cellular modem is that you can’t use the GNSS without revealing your location. All cellular modems reveal your location, so you can never expect to use a cellular modem without revealing your location. Removing the GNSS functionality from the modem merely limits the precision with which it can reveal your location.
Although the Librem 5 will have a separate GNSS chip, its modem will still contain GNSS functionality. It’s just that Purism is not going to use that functionality or connect it to a GNSS antenna, so it will lie dormant.
They should publish a FAQ answer for “Why is it so gosh darn expensive?!”