Docker solves a different problem. Docker is a way to basically ship your whole OS off to another machine. You still have to have a way to install the right version of python and all the python libraries you need inside the Docker container, and uv is great for this.

Secondly Docker only solves a subset of problems. It's fine if you're developing a server that you will be deploying somewhere. It's inconvenient if you're developing an end user application, and it's completely useless if you're developing a library you want people to be able to install.