The Kueda link stats are with regard to RG data.
I’m sure I dug through the links to the museum/herbarium accuracy comments previously… it just ended up at a single anecdote that has been regurgitated over and over since then in a way similar to this thread. I don’t believe there was ever a solid source, though it would be great to see one / be proved wrong.
The idea that iNaturalist accuracy will compare to museum accuracy seems conceptually doomed from the outset to me. At least in the UK, something like the Natural History Museum has the largest collection - with the bulk of our type specimens and the bulk of our taxonomists. These are literally the people making the keys and staking out the information we are using to make IDs here! It seems really counterintuitive to think that iNaturalist accuracy could be likely equivalent to museum collection accuracy in its current design.
In taxa where we have experts such as those from the NHM engaged on iNaturalist - like Tachinidae - we have similar accuracy, sure. In taxa like millipedes, where we have almost nobody active, we seem to have very little accuracy. It’s just inevitably going to be patchier.