I agree, it also goes against the Linux "way of doing things".
For example, Opnsense uses the dhcp portions of dnsmasq only (and unbound for the dns parts) which just feels 'wrong'.
Is that the Linux way you are on about? No obviously not 8)
I think you mean the "unix idealized but never really happened exactly but we are quite close if you squint a bit ... way" where each tool does one job well and the pipeline takes up the slack.