I find curly hair fascinating especially those with volume and how they react when slime is poured over and it just collapses under pressure.

For reference:
https://the-slime-and-pie-show.umd.net/download_info/lane-slopped-and-slimed
https://dl.messygirlvideos.com/cgi/autogal.pl?vidnum=tws-75-1115

I rarely see this in WAM which I could understand why, but I would like to see a black girl with their natural curls and hairstyles getting messy.

You might like Friday's work for us, she's happily allowed her gorgeous curly hair to be very thoroughly messed up on multiple occasions, and she's drop dead stunning too.

https://saturationhall.umd.net/downloads/model/friday

I'm 100% with you here! There's nothing I love more than seeing a pretty girl's thick curly hair reduced to a matted down mess by falling slime. But, as you said, it's very hard to find - and understandably so. Even the MG video you linked to is a wig.

You might like this video Larz did for me? She isn't wearing a wig (as far as I know) but her hair is relatively thick. https://theslimecave.umd.net/download_info/arias-christmas-special

(I actually requested her for a custom because she appeared elsewhere with big curly hair, but it turns out that was also a wig.)

No real opinion on it in WAM.

On the other hand, curly hair straightened or curled hair makes me feel a certain way.