I would assume you are speaking mostly about old historics and not newly introduced cultivars. With new stuff, there is a lag between the time the hybridizers post it on their websites and when the information is published by the AIS (American Iris Society). And that is the source we use for this site as to definitive data resource (I could be wrong and await an administrator to verify).
I agree with you if a poster is SO blatant with multiple pictures that are wrong, that their all of their future contributions would be quarantined and not posted to the cultivars until vetted by an administrator. Furthermore, If feel that all of that posters contributions should then be reviewed for the same problems/issues. If that too is found to be suspect; then I feel that all of their contributions should be removed/quarantined until the issue is resolved. But I am not an admin and I do not know what the proceedures are for this type of issue.
Did some of the pictures you are questioning have signs with names on them? Like they were at some botanical garden? Could it be that the poster is posting mistakes made by the place they visited rather than purposefully doing it on their own? has this person responded to any inquires about their postings?
