Se a pergunta for "por que arch sem systemd", essa é a resposta.

TL;DR

systemd is a replacement for the sysvinit daemon used in GNU/Linux and Unix systems, originally authored by Lennart Poettering of Red Hat. It represents a monumental increase in complexity, an abhorrent and violent slap in the face to the Unix philosophy, and its inherent domineering and viral nature turns it into something akin to a "second kernel" that is spreading all across the Linux ecosystem

Desde sua criação ha esse movimento de boicote a ele, pelos princípios listados nesse site, que já morreu mas permanece sendo citado até hoje.