I ended up having to flash Lineage, as there was some outrage that in a highly limited set of circumstances, thin see-through T-shirts became slightly more see-through and OnePlus disabled that camera in their later firmware updates.
Nowadays, there is a more mature ecosystem, with specialized drone mapping cameras tailored for the purpose.
For our use case, the micasense rededge would have been perfect.
CMOS image sensors are naturally sensitive to near IR. Early feature phones had no IR filters on their cameras - you could see an IR remote light up through them. But as people became more and more obsessed with smartphone camera quality, smartphones started to ship with those filters too. You get more "lifelike" colors that way.
Although in some multi-camera smartphones, one of the secondary cameras may lack an IR filter.
Ironically, older iPhones have better depth resolving capability overall. Apple sacrificed depth sensing performance in favor of smaller unit size in the newer ones.