I don’t think location necessarily needs to be required for CV to work, though I don’t really see any reason why it shouldn’t be as all iNat observations should have a location. That is the most logical/useful solution.
If that can’t be implemented, I do agree that a prompt when trying to add an ID when there is no location entered yet would be useful. Something like “ID suggestions may improve if you add a location first”. Of course, there are currently a lot of problems with the “Expected nearby” suggestions, but hopefully the geomodel issues that have caused that will be fixed soon.