No need for his merit to be removed. If truly the person used AI and people agree to it, why not just leave him neutral trust and state the reason and put the reference link. It is better this way.
Well I wouldn't agree anyway with your suggestion even though it makes sense because they have been an existing pattern of stereotyping shit posters of AI content generators which Charles-Tim mentioned above and probably even though such user emerges as a higher ranked member he's still going to be know for such actions because the trust system keeps it open to audience to see his tags, which is enough punishment for me and reducing the merit or deleting the already earn merit from them is not what I think.
I know about that, but as I have observed; neutral feedback or trust mostly doesn't stop them from participating in bounty campaigns and they would still rank up, join them, and keep doing what they are doing unless they get banned, and in most cases, users aren't banned for doing something that gets them a neutral trust. Bounty campaigns usually only has
a rule against red trust and say nothing about neutral trust.
Just because someone has managed to get the required merits doesn't necessarily mean that they are going to get accepted into signature campaigns. The neutral trust on their profile gives campaign managers the right information about the account and I don't think any campaign manager would want to hire a plagiarist/AI spammer. The campaign you referred to has removed a participant that was caught plagiarizing, that’s one of the cases that I am aware of.