It's fine when it works, but it's very hard to solve problems when they happen as it's so complex, and doing stuff outside of "the standard thing" can be difficult.

I once had "systemctl restart unbound" reset my volume, consistently. How do you even start debugging something like that without a deep dive in systemd? This particular issue turned out to be a systemd bug, and that such a bug can exist in the first place didn't exactly increase my confidence in the system.

In another case I couldn't get my NFS to work at all, and it turned out that rpcbind.service somehow went missing. Not sure how that happened and it's a simple enough problem, but it was really non-obvious because systemd doesn't issue clear errors on this and the system is so complex it's not easy to spot either.