IMHO none of those should be reasons for a name change. typo or spelling error, well lets just say you should have thought of that before you finalized. however, you could just redo it with a new email. if players are harassing you then you should contact customer service instead because you are most likely not the only one to whom he is doing this to. account trading is forbidden. the other points are just rephrasing and redundant.
i think this option is not given to actually prevent abuse for almost the same reasons.

that all being said, i strongly believe that the GM's should pay more attention to the created names and should add a word filter. some names you cant even write into chat without getting the **** instead. on our server some guy thought it is funny to create names like " > ". everytime > shows up in chat it bugs the chat and for example when > does something on the high seas the entire history gets erased.
however, those are just examples why manual scans should also be added to catch players that avoided word filters by misspelling or adding graphic-lettering. there is some really offensive names on our server alone and i can only imagine how bad it is on some other servers.