Putting aside the speed uv has a bunch of features that usually require 2-4 separate tools. These tools are very popular but not very well liked. The fact these tools are so popular proves that pip is not sufficient for many use cases. Other languages have a single tool (e.g. cargo) that are very well liked.
You should check out zig, its compiler can even be used for c/c++. If you have time to listen to an interview, this developer voices interview on zig explains some of the advantages of this: https://www.youtube.com/watch?v=5_oqWE9otaE&t=3970s