I don't know of a specific theme in the neubrutalism/neobrutalism style (names that are generally used to describe this style or aesthetic), but it shouldn't be too hard to make.
For anyone unfamiliar it's generally defined by flat, blocky layouts, with thick borders, single color drop shadows and a few bold high contrast colors (think CGA and EGA monitors if you're that old). It often features “unpolished” elements like flat simple shapes. Bold fonts and monospace fonts are pretty common.
There are a few resources out there if anyone wants to play around with this style.
https://github.com/ComradeAERGO/Awesome-Neobrutalism https://dribbble.com/shots/20764973-Neobrutalism-UI-How-to https://www.nngroup.com/articles/neobrutalism/