> IMO there's no point having a clean history of commits within a PR. With rare exceptions, if you have a PR with a clean history of commits and each commit compiles and passes the tests... they should be separate PRs! If it isn't clean then it should be squashed.

I think that whether clean history has a point, really depends on how deep are you refinement sessions. And perhaps a bit on the general health of your codebase.

If you don't do refinement with your editors open and grind tickets into dust, there will be side-changes adjacent to each PR which are not directly related to the ticket. These are better to have their own commit (and commit message).