Would it be possible to prevent nodes being added at "null island"

[SomeoneElseOSM]

Example:
https://www.openstreetmap.org/changeset/44843603

If the obtained location is lat 0 long 0 it is extremely unlikely that the user is servicing the weather buoy there - much more likely that their phone has not obtained a location yet.

[SomeoneElseOSM]

It still happens occasionally - see https://www.openstreetmap.org/changeset/49668409 .