Check the size of the gap between the bottom edge of the tailgate and the flat horizontal surface of the bumper before fitting one of these protective strips - especially if it’s from a third party manufacturer.
Some Golf owners on various forums in the past have had issues with the lower edge of the tailgate/ hatch making contact with the flat horizontal surface of the bumper when opening and closing the tailgate / hatch, resulting in the paint being removed from either the bumper or lower edge of the hatch. And that’s without a protective strip fitted to the bumper that could reduce the size of the gap when the thickness of the strip is taken into account - that black bumper protective strip looks to be a few millimetres thick, so fitting it could result in rubbing issues.