Theoretically the names and the very memories of evil people (rasha'im) should be obliterated. Is this aim seriously pursued? For example, saying ימח שמו after a name doesn't really help obliterate ...
Why have there been famous(ly righteous) Jewish people named after Yishma'el, who, Chaza"l tell us, was evil and an enemy of Jews? Has anything similar happened with Esav? Korach? Others?