I know when I am agreeing with an ID, I am generally just looking at the taxon name, and not always noticing the agree/disagree status of that ID.
So at the very least, I think I would want to be asked the same question that the original disagreeing IDer was asked, to confirm whether I want to lodge the same disagreement, or just agree with the family name and not explicitly disagree with the earlier species ID.
That topic was saying the CID calculation was incorrect, though it was correct based on the IDs.
This topic could alternatively be a feature request I guess? I went back and forth between where it should be placed. What I meant by expected behavior here is that if I were joining iNat today, I’d expect agreeing with a disagreeing ID would also log the same disagreement.
This is related to an issue that was brought up in another thread where deleting ID1 would also remove the disagreement for ID2 and ID3 in your example.
Not sure if it is truly a bug or a feature request, but it would be nice to not have that counter-intuitive behavior.