After D11036, we try to run as the configured `phd.user` and raise a setup check if daemons are running under the wrong user.
If we aren't able to switch to the correct user with `sudo`, we still launch the daemons (as the wrong user, with a warning). This gives installs with bad configuration some time to fix the problem on their own without anything breaking.
Once installs have had some time to address the issue (say, after a couple of months without anyone raising support issues), we should make `phd` abort the launch if it is unable to launch as the correct user.