Species ID errors in difficult taxa?

You should not delete observations just because you don’t agree with the identifications that other users have posted. In many/most cases, these will work themselves out in time as other users chime in. You can also leave comments asking users to explain their ID/explaining your identification to start a discussion. You can tag other expert users asking them to chime in (though this should be done with discretion, and not spamming other users).

I would suggest not getting hung up on Research Grade. Even non-RG observations are accessible to others (just not via GBIF). In some cases, observations don’t reach RG for years.

As far as any specific observation being used, that’s hard to know, but iNat data have certainly been used in publications. You can check out non-exhaustive lists: