I think It’d be nice to have two new location concepts:
First is “You’re a fixed node, I’ve told you your location”. It would be ideal if nodes had a concept of a “remote administrator”, someone who can cryptographically authenticate and change settings that others cannot, as per this thread. Although perhaps even this setting should only be a “suggestion”, in case the node walks off (is stolen) and later discovers, via high-confidence means (like bluetooth connection to a GPS-equipped node) that it’s far from its supposed position. (And likewise, a setting for “alarm if location changes” would be awesome.)
Second, is “pseudo-location” fixes, as already described in this thread. Where a node without GPS infers its location based on the RSSI of several other nodes that do have GPS. Obviously if it’s connected over Bluetooth, that counts more strongly, maybe increase the confidence score of the pseudolocation, since the other node (be it a phone, or a GPS-equipped T-beam also talking over Bluetooth) is likely very nearby. But even just using Lora links, having a vague idea of where the roving node is, could help you get in the ballpark and get into Bluetooth range, etc. For when a node you weren’t expecting to become mobile, suddenly is…
There’s another use-case for RSSI-based location, where the real-world position is actually less relevant than the radio-connectivity-based estimate: Geographic routing protocols! Obviously not a thing in meshtastic yet, but there’s plenty of prior art for how location-aware networks can do near-optimal routing without a full view of the whole mesh. Having every node know its “position”, even if not GPS-informed, would pave the way for such enhancements in the future…
However, yeah. All this comes with huge cost in complexity, which likely exceeds the hardware cost of GPS chips. Especially as the latter keeps falling.
The question there is whether a Lora-based estimate would be any better than the GPS chip’s hopeless guess. Modern GPS chips are pretty good even in challenging situations, in my experience.