Also curious what you dislike so much. And how does Photoshop compare? https://i.ytimg.com/vi/_ghez_hKxeo/hq720.jpg I like the way Gimp has looked more and disliked many of their experiments changing things. The screenshot you linked isn't even the default look anymore, they've got a dreadful dark mode if you like that sort of thing. The first thing I do on a new install is restore the light mode and color icons it has, and make all the tool icons visible at once.
Your argument in favour of Gimp is that its default UI is dreadful? (I agree, but it's the fault of the Gimp UI, not of dark modes in general.)
I don't like its default look, but the screenshot they linked was non-default and what I do like, so I'm wondering why they find it sloppy/bad. Perhaps they would like Gimp's default more? Here's a representative shot from 2020: https://www.lifewire.com/thmb/H9QCFUVFrU035srbCoZ5erwS20Q=/1... Not even the +/- buttons another comment complains about are in this one.