I see where you’re going with the prudish thing, and it’s probably partial right.
The era when Mickey and Minnie were created though actually had a lot of sexual references in those times in film. But once the 50s came, it changed. You know, showing married characters sleeping in seperate beds. THat’s the era when Disneyland opened and Mickey was at the height of popularity. So clean morals probably does have some say in this I suppose!