Does that happen on merge or before PR creation? I thought the setting only applied it when you hit the merge button, so you'd still have commits prior to the merge. Though that won't help if someone pre-squashes them :s
If you, however, open a chain of 8 PRs, and merge them in the right order, the individual commits will be persisted in the git history. Potentially worth it if you like to have a "story" of several commits...