Using the system Python for development comes with its own problems. That Python is both an interpreter required by the system for numerous scripts and a runtime dependency for other packages. Using that gives people all sorts of problems, especially when "sudo pip install" is used. You can even break a system that way.

Gentoo is the only distro on which I feel comfortable using the system interpreters because the versions are slotted (you can have multiple versions) and system pip install is effectively disabled.

So on other distros I use pyenv. But trying to explain this to non-Linux geeks is hopeless.

I've taken to recommending the following: use system python/pip to install pipx (but with --user). Use that to install "global" tools. Use virtualenvwrapper to manage projects. Use pip-tools to manage frozen environments (ie. requirements.txt). I've looked into replacing the latter with pipenv (which is awful) and poetry (which is better) but I've so far been unable to generally recommend anything else.

I don't even want to think about other platforms and conda and all that.

I agree that there are potential problems w using system Python - the way I've had it work is to only support a recent Ubuntu distro and its Python version (latest LTS) and use the Python 3-included venv module for making a virtualenv. But yeah Docker is easier and more widely compatible, and works on Mac/Windows too.