For what it’s worth, my experience with prolific identifiers (those that populate the leader boards), is that most of them are pretty helpful, and the site would benefit from more of them.
From time to time I do notice what I might consider overzealous identifying, but usually they aren’t up that high on id totals yet. Where I am at, the things that get attention (mostly birds, mammals and to a lesser extent vascular plants, marine algae and some intertidal organisms) are getting that attention primarily from prolific identifier. Most of them seem focused on particular taxonomic groups (perhaps within a fairly broad region), and a couple seem focused on intertidal invertebrates a little more generally.
I am also a prolific identifier, though I focus on an area rather than group. Part of my personal motivation for doing identifications is out of a sense of reciprocity for the help I’m getting from others identifying things I’ve submitted (I tend to aim for about twice as many IDs for others as I have observations). I also enjoy seeing what’s out there for me to look for in the future, and learning more from what other are seeing.
My approach is to look at everything in a specific geographical area, centered on Southeast Alaska (all of my observations are from this region, with the vast majority from the Sitka area) - but spanning coastal areas from Haida Gwaii to the Aleutian Islands without regard to taxa.
Each day I try to look at every new observation (I have bookmarked the identify page for the patchwork of locations that make up this broader area), and identify everything I can (being more conservative the further away something is from my core area).
As a result, I’ve accumulated many IDs and have become top identifier in multiple different taxonomic groups, not because of any particular taxonomic expertise on my part, but because I’ve learned what occurs in my area, and if it’s something that’s pretty common, I end up with a lot of IDs, even though I don’t actually know how to identify the organism from other similar looking ones that might occur elsewhere (in many cases, I don’t even know if there might be similar species elsewhere).
Incidentally, I do get tagged from time to time because I’m on the leader board for the species, and if it’s outside my area (it usually is) I politely decline to offer an ID because I can’t really confirm outside my geographic area.
I do benefit greatly from those folks who focus on a narrow slice of taxonomy with little or no geographic constraint, and contribute to observations in the area I cover. Their IDs help me better understand what occurs in my area - and there are several I can think of who I’ve come to appreciate for their knowledge and help.