It's a pretty good example of why people think systemd is bloated and does too much. It's a simple boot entry multiplexer. Does it need to live in systemd's tree?
so its a marketing problem, irregardless of whether it's in systemd's tree because the systemd maintainers want to maintain it in-tree
Nobody complains about a very wide variety of only vaguely related utilities being in the Gnu coreutils tree.