I wouldn’t say obscured data is “useless”, just less useful/used less.
There is a “batch edit” functionality which I think can change obscuration, location, and accuracy. I’ve never used it so I can’t provide detailed help, but you could try searching for threads about batch edit and seeing anyone has used it for similar before. Here’s one to start with:
https://forum.inaturalist.org/t/is-there-a-way-to-batch-edit-my-old-observation-locations/28996
You could try changing the “true” location and accuracy first and then, once you’re satisfied, taking off the obscuration.