The git push --force is definitely a controversial suggestion, im personally happy with doing that, but I have also personally accidentally force pushed dev/main and seen others do it. Squash on merge is probably a safer habit to have. Also, gitlab and bitbucket both get a bit confused if you forcepush to a branch that is part of a MR.

You can add branch protections that will prevent you from accidental force pushing to main or dev.

IMO when I see a PR with “WIP” commits, I just assume that minimal effort was put into keeping the commits organized, and I squash all commits to review the PR. If I see many meaningful commit messages, I will try reviewing one commit at a time.