How can one fully replace distutils, which is deprecated in 3.10?

Question

Yes setuptools can fully replace distutils for everything
distutils.core.setup maps to setuptools.setup
distutils.core.Extension maps to setuptools.Extension
setuptools is not part of the standard library (hence its absence from the doc) but it is part of the standard python.org distribution.
some distributions choose to separate setuptools and pip from the default python package because they don’t assume you will be using python for writing code, however some system tools require python (apt among others). If you plan to use the distribution as a development tool, you are expected to install pip and setuptools from the distribution repositories.