there are multiple types of disagreements. so instead of just =true/false/any, i think if this were implemented, it should allow differentiation between normal disagreements and (potentially different types of) ancestor disagreements, too.
i think in a way, this is very similar to https://forum.inaturalist.org/t/url-parameter-to-exclude-taxa-by-identification/30266 and other new features requested in the past, though each approach has their pros and cons and potential set of use cases. i think these kinds of requests just go to show how many different identification workflows there are out there.