I think the cool thing about Rap is the technical prowess required to do it well. Think about it, you need multiple verses at 16 bars and each bar has to rhyme and you can’t repeat verses and if people find out someone else wrote the verse you are ostracized.
Look at the average Nas verse, it has more lyrical content than some entire Rock songs. Then you add in the Hooks and the requirement to rhyme and you have an artform infinitely more challenging to write. Rap needs its flowers, it’s such an awesome genre of music.
Other genres require the ability to have vocal range and perfect pitch but it balances or becomes even easier by not requiring long verses, someone else can write your music, and not having to rhyme.