You realize it needs to be done, right? :/ You realize this attitude is likely what prevents it getting done?
I’m sure I’m not the first person to go through that experience, and; again - this needs to happen in the actual build, not a fork.
Stepping in with a replace-the-whole-UI idea is generally combative in nature and may engender combative responses. Rather than being surprised at the response, maybe think about whether what you did might cause it.
By odd analogy, it's like you're starting a career as a traffic engineer and immediately demanding the road surfaces get replaced, without demonstrating an understanding of why the road surface is the way it is or why projects to replace the road surface tend to fail.
(I'm not involved with the project, so my attitude doesn't matter and you don't need to worry about what I think.)