I believe that would open a non-draft PR (which for me gets announced on Slack which I don’t want) unless you enter flags which I don’t want for daily commands, opens it against the wrong (master) branch in my case, and takes me to the wrong page (convo/main) whereas I want to see files. It’s not a bad alternative.
Same issue with Slack. IMO the PRs should be by default opened as drafts, or at least there should be a per repo or per user option to enforce that.
Often someone opens a nonreviewable WIP, or messes up something with branches, and dozens of codeowners get pinged to review a diff of something that was already merged.
Also even if initial PR is flawless, it doesn't hurt for the opener to take a deep breath and self-review it before notifying everyone.