The problem is that they’re trying to frame it as a better replacement for sudo when it’s really not.
In some respects, it’s safer by not using a setuid binary. In other respects, it massively increases the surface area by relying on the correctness of three separate daemons: systemd, dbus, and polkitd. If any one of those components are misconfigured, you risk an unauthorized user gaining root privileges.
With sudo, the main concern is the sudo process being exploited through memory safety bugs since it runs at root automatically.
Don’t get me wrong, sudo has a lot of stupid decisions and problems. There’s a ton of code in sudo for features that almost nobody uses, and there’s bound to be bugs in there somewhere. It needs to be replaced with something simpler, but run0 is not that.