@fohrloop Huh. I did a quick experiment which suggests otherwise:
>>> from packaging.version import Version
>>> from packaging.specifiers import SpecifierSet
>>> s1 = SpecifierSet("==2.2.0")
>>> Version("2.2.0.post0") in s1
False
>>> Version("2.2.0.post1") in s1
False
>>> Version("2.2.0") in s1
True
(".post0" is the canonical way of writing "-0", and so on)