I don't think the last name "Pot" is going to be clearly associated with any protected class. If they where banning all last names prefixed by "O'" or the name "Rousseau" that'd be a bit different.
Yeah, this is kind of the issue; I don't know if "Pot" is indicative of any clear nationality or heritage.
Kind of a lacuna in the law--I think almost everyone in the country would agree this person has a legit grievance here, but not sure what the exact legal theory would be...
The victim can sue due to damages, but it's still just a name.
I believe there's someone running around with a first or last name of literally "null" who has problems regularly. They should absolutely be able to sue, but there's no way in hell someone is deliberately did that as a result of even neglectful discrimination. It's just poor engineering.
Hijabs and turbans are not protected classes either, but religion is.
In this case, one would argue nationality, probably, but I'm not sure what the strength of a lawsuit would be or on what basis.