I've been using systemd on most of my systems since it was released; I was an early jumper to upstart as well.

The thing I don't like about systemd is how pervasive in the OS it is. It violates the "do one thing, do it well" Unix philosophy, and when systemd went from an init system to starting to take everything over, I started liking it less.

My issues with systemd is that it isn't an unmitigated success, for me. journald is horrible: it's slow and doesn't seem to catch everything (the latter is extremely rare, but that it happens occasionally makes me nervous). There are several gotchas in running user services, such as getting in-session services working correctly (so that user services can access the user session kernel keyring).

Recently I've been using dinit on a system, and I'm pretty happy with it. I may switch all of my systems over to it; I'm running Arch everywhere, and while migrating Arch to Artix was scary the first time, in the end it went fairly smoothly.

Fundamentally, systemd is a monolithic OS system. It make Linux into more of a Windows or MacOS, where a bunch of different systems are consolidated under a single piece of software. While it violates the Unix philosophy, it has been successful because monolithic systems tend to be easier to use: users really only have to learn two command-line tools, vs a dozen. Is it categorically better, just because the user interface is easier for new Linux users?