For that use case, I don’t think the class should be called a loose version. It’s not loose, it’s conforming to a different standard than PEP 440. Or call it something like GenericVersion with documentation explicitly noting that it’s for parsing versions of non-Python projects.
If the use case you’re targetting isn’t parsing old, pre-PEP440 Python package versions (the transitional case I assumed was the intention) then the fact that it’s historically from distutils is basically irrelevant at this point, and the current documentation needs updating to note that Python packages are not the intended use for this.