Systemd was easy for me. All things worked in transition and have the big advantage that don't need shell scripts for create services. Wayland..., is slow, buggy, applications close without reason...

systemd was a problem for early adopters (e.g., Fedora). Distros like Debian joined the party later and, as a result, got things way more stable. I never had any systemd-related problem in Debian, while for Fedora (some years earlier) I had some bugs affecting my ability to work. They all seem to work very fine now. Things took a while to mature, but it just works now.

I haven't had a single issue with Systemd and the transition was measured in years, not decades.