Nothing as dramatic as an ant / moose misidentification, but I’ve seen the following:
Cervus canadensis - common name is “wapiti” on iNaturalist, but most people in the USA call them “elk”.
Alces alces spp alces - common name is “European Elk” on iNaturalist. If you type in “elk”, Alces alces will also show in the dropdown.
Sable antelope (a type of antelope) and the sable (a small carnivore related to wolverines and martens).
Wild horse (Przewalski’s horse / Equus ferus) and the domestic horse (Equus caballus). A fair number of observers think they’ve seen Equus ferus. In reality they saw a feral population of Equus caballus that are colloquially called “wild horses”.
And yes, I look for disagreements to try to resolve them. Sometimes I go to the species taxon page and look at the “Similar species” aka common misidentifications.
Other times I use the Identify tab, type in whatever taxon (for example, Equus), and click the “disagreements” box to search for disagreements (for Equus, I’d look for obs stuck at the genus level and look for photos that appear to be horses or donkeys. A lot of zebra photos will show up and I don’t know how to differentiate zebra species).
I’ll look for comments as well especially on the more recent observations, even if the community taxon is at species level, just in case the observer or anyone is confused about the community ID.