Well, start up problem is a matter of convenience, it's not a fatal problem, but I just like that my laptop with arch+systemd+systemd-boot starts instantly (3 seconds + 6 seconds for firmware), while bsd on my other laptop starts soo damn slow. (btw slow shutdown pisses me off even more)

Though the real issues with rc are much more serious, and eloquently described here (aka you don't have proper login management, service management, device and policy management, and better in a unified way):

https://www.youtube.com/watch?v=6AeWu1fZ7bY