There are a lot of ways to interpret "convert to bool" - should "yes" and "no" be converted? What about "1" and "0"? Or "001", or "-1"? What should happen to unrecognised values? What if the environment variable doesn't exist? It's not at all obvious to me that strtobool is the definitive way of doing this (quite apart from the fact that distutils will be getting removed from the stdlib in Python 3.12 - see https://peps.python.org/pep-0632/).

What is so special about *this particular way* that it's worth including in the stdlib? Particularly when it's so easy to write for yourself.