Pull Requests are just a tool
The developer experience you have around the pull request is a function of your dev process, not the tool itself.
- See The correct response to complexity is probe, sense, respond for how PRs can hinder the "probing" phase if they are used as a gate-keeping tool
- See Agile practices only make sense when iteration is cheap for how PRs can make iteration and quick feedback more expensive if they are open for days