I am not sure how much power Debian have if projects start to depend on systemd outside of initialization. Things like socket handoff, service discovery, loggin

I am not sure how much power Debian have if projects start to depend on systemd outside of initialization. Things like socket handoff, service discovery, logging and so on is choices of upstream and can be quite convenient depend on which ever third party library that is most common in use. Good programming practice is to make it easy to change components like that, and doing it also helps testing. In theory it should just be a matter of replacing a few components to get gnome running without systemd, depending on how hard coupled those are.