No, it does not have a bug.
The systemd upgrade in this update is a major upgrade that can crash the graphical session, including all apps open in the graphical session (including Pamac or Terminal). This has been experienced in Unstable and Testing also.
If Pamac or Terminal is crashed mid update it can potentially leave a system in an unstable / unbootable state, requiring chroot into it to remedy.
This is why in the second thread post users were instructed to perform this update from tty, and given explicitly easy to follow instuctions on how to do this. There is no graphical session in a tty terminal, so updates can complete unhindered.
Bottom line is to read the second post in every announcement thread, it contains important information relevant to its specific update.
Those inexperienced users trepidatious about applying such a big update, don’t do it immediately. Wait a day or two. Read this thread and learn from potential issues others have had. That way if you experience the same issue you know how to resolve it yourself.