[throwaway82652]

>IOW, if I build a system with yocto for an embedded system, which is also a very useful candidate for a read-only system image installation, I cannot use this feature for this use-case because ... yeah because what. Because lennart says so.

No this is wrong. You can still use this feature but you get to manually type out all the mount paths yourself every time and work out all the bugs in it when you try to mount other things on top of it, because that's what you signed up for when you decided to have multiple paths. I'm really baffled as to how you could even remotely say this is a systemd problem. This will be a problem if you try to do any kind of bind mount or overlayfs stuff on that system.

I really suggest that you avoid making comments like "systemd uses its gravity to try and shape linux distributions and dictate how things 'ought' to work". That stuff is conspiracy theory territory at this point, it's so disconnected from reality that it's just pointless to say it.