> If you don't like this risk, you need to work in persistent storage.

Which is literally what /var/tmp is and what the parent is advocating for.

However, clearing /tmp at boot is not the greatest technical choice. There's nothing really special about rebooting the system. The idea that files in /tmp are kept around for anywhere between minutes, hours, and days makes for bad policy which systemd-tmpfiles fixes quite elegantly. You shouldn't lose your temp file after 30 seconds because your machine lost power. You should be able to say "files created here are cleared after $short_time of inactivity."