Sister wants to name their son Makenzie

I saw a post on here about names and parents being ridiculous in their names. Well my sister's son is gonna be here in like a week and she wants to name him Mackenzie. I said that's a terrible idea since it's a female now. She argued that Mackenzie is unisex and in Scotland where her husband is from Makenzie is a BOYS name. She also thinks that with shows like Bluey that have a male character named Mackenzie by the time their son is in school it would be normalized. I don't know. I was bullied a lot as a child and and don't want that for my nephew.