Perhaps a case for standardizing on an executable name like `python-script-runner` that will invoke uv, pipx, etc. as available and preferred by the user. Scripts with inline metadata can put it in the shebang line.
I see it has been proposed: https://discuss.python.org/t/standardized-shebang-for-pep-72....
I get the impression that others didn't really understand your / the OP's idea there. You mean that the user should locally configure the machine to ensure that the standardized name points at something that can solve the problem, and then accepts the quirks of that choice, yes?
A lot of people seem to describe a PEP 723 use case where the recipient maybe doesn't even know what Python is (or how to check for a compatible version), but could be instructed to install uv and then copy and run the script. This idea would definitely add friction to that use case. But I think in those cases you really want to package a standalone (using PyInstaller, pex, Briefcase or any of countless other options) anyway.