Those manual interventions were not that frequent before so Arch was easy. Lately it has become more of a hobbyist distro you need to invest time where other distros simply are the foundation of your work. A lot of devs use Arch so then it actually is work
Doing it like this enables Arch to move fast.
A lot of changes are going on in the Linux world and if you want to be on top of it - Arch is the distro. And f you want all the latest software it will be in Arch.
But Manjaro is close and I bet it will pass Arch on the Distrowatch list soon.
What makes Arch really great is the pacman package manager - it is the best.