If you try to keep your depencies low, it's not very cumbersome. I usually do that.
A setup.py/pyproject.toml can replace requirements. txt, but it is for creating packages and does way more than just installing dependencies, so they are not really competing.
For scripts which have just 1 or 2 packges as depencies it's also usuall to just tell people to run pip install .
If you try to keep your depencies low, it's not very cumbersome. I usually do that.
A setup.py/pyproject.toml can replace requirements. txt, but it is for creating packages and does way more than just installing dependencies, so they are not really competing.
For scripts which have just 1 or 2 packges as depencies it's also usuall to just tell people to run pip install .