Apart from the comparison to NTDLL making no sense, you'd be wrong about the tools too. It aims to provide a basic standardized way to do most system-level management (set up networking, do DNS resolution, get a decently synchronized system clock) but it absolutely does not aim to replace more specialized tools like chrony or NetworkManager. For example, timesyncd doesn't do NTP or PTP, only SNTP.

systemd (the PID 1), journald and udev are different, though, because they're mandatory; and there's no alternative to logind while technically optional.