There would be no Madonna without Marilyn Monroe, and thus no Miley Cyrus, no Lady Gaga, no Britney Spears.
Again, there is nothing wrong with being waifish, rail-thin, etc.
She gave up her easy life of being the heiress to the Oh Henry candy bar fortune - and showing her bra in public - to become a starship captain of the Federation, taking the fight to the bugs across the galaxy.