From a moderator's perspective: let's indeed leave this tangent behind and go back to discussing the repair of this particular camera model. Thank you.
I've held two 7sii's, one 35ES, and even a Prinz 35ER, and they all had that little bit of play. It doesn't affect anything at all about the function/performance of the camera, thankfully, so it's all about moving past it on an emotional level. Which is perfectly easy to do until I pick up my Hi-Matic E and my brain goes back to "this camera feels rickety" mode with the 7sii.
Yeah I handled a Auto S3 which had the same issue. It's annoying but no big deal in practice. At least the S3 has built-in notches in the helicoid keys.
BTW I managed to modify the GN system for an approximate manual aperture control. The GN coupling seemed way off anyway.