Everything Corbyn is trying to do could be done under "soft Brexit" and you know perfectly well that if the UK gets of the human rights, labour rights and environmental protection agreements, those protections will never be re-established on a UK-only basis. There would never be anything close to them that would get through parliament and not simply repealed next time there's a Tory government.
That is a good summation of what Brexit is about, namely, getting rid of the EU's human rights, labour rights, and environmental protection agreements.