While the rest of systemd is actually pretty modular, journald is unfortunately the only other required component. You can not run systemd without journald running in some way; closest you can get is setting Storage=none and forwarding the logs elsewhere.

journald is in a weird state where its "good enough" and mandatory that most people forget how bad it is until something like this pops up.

Normally I'm pretty happy with systemd and its many components; I even willingly run systemd-resolved, which is probably the other most hated component. But journald makes a lot of weird choices and if I could drop it I would in a heartbeat.