I think I understand the reasoning behind the strict usage of pip and the Python version usage, keeping things less complicated & without much surprises. On the other hand, keeping it safe with not using the latest stable Python is sometimes painful. New features are often good things for development and code readability, such as the quite new merge dictionaries syntax and less verbose usage of the typing module.

Keeping it simple with only using pip would work for the more straight forward & simplistic kind of projects. But you would probably want something like Poetry to have a nice Developer Experience - and the abilities of Poetry plugins like Polylith to handle monorepos and sharing code.