Since version 3.34, GNOME has completely switched to the systemd user session toolkit. This change is completely transparent to both users and developers (XDG-autostart is supported) - apparently, that's why it went unnoticed on the ENT.
Previously, only DBUS-activated were run by user sessions, and gnome-session did the rest. Now this extra layer is finally got rid of.
Curiously, during the migration process, systemd added a new API for the convenience of GNOME developers - https://github.com/systemd/systemd/pull/12424
It's nice to see when open projects are ready for cooperation and meet the wishes of users.
From myself: I switched to KDE for reasons unrelated to the news topic, but I still follow the development of the project and sincerely hope that other DEs will follow GNOME in terms of session management unification.
Source: linux.org.ru