A venv does not actually install a different Python interpreter. It's bound to the Python version that created it. You cannot make a Python 2.7 venv using a Python 3 interpreter. You need Python 3.10 to create a Python 3.10 venv.

There are plenty of situations where the Python interpreter version matters. As a non-exhaustive list, you have libraries that compile code, non-Python languages that link to cpython, build scripts that do different things depending on wheel/setup/other-bundled-stuff, Python code that uses removed compat shims like importlib-metadata...

If you haven't run into one of those situations yet, congratulations. I've been through this already, and making a reproducible environment does require first installing a pinned version of the Python interpreter and THEN setting up a venv using that particular interpreter.