To be honest, Caulifa does look pretty shitty when you first see her.
She barely looks like a DB or DBZ character to be honest
Bulma had more meat on her when she was 16 years old in Dragonball
Main problem with all the new saiyans (Universe 6) is that they don't match the aesthetic of the old sayians (Universe 7).
DB had a different aesthetic than DBZ, while DBZ now has a different aesthetic than DBS. DB had more cartoonish proportions, rounder body shapes and whatnot. Only really a handful of characters were muscular and none to the level you'd see in DBZ. DBZ started with the DB aesthetic until around the Freiza arc, where we started getting the super bulky style of the characters we all know now.
With DBS, the newer characters, especially the saiyans, are back to the cartoonish feel of DB, but instead of rounder bodies, we're getting lankier ones. Cabba is supposed to be one of the elite saiyans of his universe, but has less muscle mass than Kid Trunks. SSG originally had Goku losing muscle mass, until that was remedied by SSB.
Having a new aesthetic is fine, but the problem that some people are having with it is that we are having two different aesthetics interacting with each other. When DB started to transition into DBZ, the cartoonish character designs were changed into their more muscular versions. Good examples of this are Goku, Krillin, and Piccolo. These characters look way different in their Saiyan arc version (the last arc to use this aesthetic) to their current versions, which showed up during the Frieza saga.
Instead of having this transition happen again from DBZ to DBS, we are just having the super buff DBZ aesthetic of the current cast interact with the lanky cartoonish new designs of DBS. Of course not all the designs are lanky and cartoonish, like Hit and Goku Black, but a majority of them are, especially the U6 saiyans. That's why some fans are comparing U6 saiyans to what feels like Deviantart characters, because their designs aren't what we're accustomed to when it comes to DBZ saiyan designs.