As someone who makes observations and identifications, as well as actually using the data (at a non-professional level), I’ve seen the different ways this affects records.
As an identifier, I’m not always going to be 100% certain when I make an ID, especially if my ID isn’t going to make the record Research Grade (I apply a higher standard when my ID is the deciding one). As a rule, I’ll either be uncertain, and say so in the comment, or confident, or certain. Unless I’m certain, it’s a bit of a concern when the observer (seemingly blindly) agrees with my ID (especially when their previous ID was Class level, or spectacularly wrong). If I am certain, I will occasionally provide links and descriptions to help the observer confirm my ID more thoroughly, and I think this helps when there are only a few identifiers for that taxon (it also gives other identifiers a frame of reference for when they disagree, or if I disagree with them).
As an observer, I will often have a more specific taxon in mind when I ID my own observation. If someone I know to be an expert confirms my thoughts, then I will agree. Otherwise I will leave my initial ID as-is, or hit up external sources and confirm that way. I don’t agree unless I have managed to convince myself, one way or another.
Finally, as someone who uses the data (in an AI-based side project), and knowing how Research Grade works, I always run my eye over the data that goes in, because I know the system often produces misidentifications, even at research grade. It would be nice to not have to do this, but I can see that improving the system will be difficult.
So how can it be improved? You could try increasing the requirements for Research Grade, but that will cause issues when there are few experts for a taxon. One thing I would suggest is adding a confirmation for when an observer tries to agree, with a short blurb on when it is appropriate (ie, “to reduce the chance of misidentification, please confirm you have taken steps to validate this ID” - Yes/Cancel). It makes it less streamlined, but I’d argue this is one situation where that’s not a bad thing.