Linux (the kernel) has LOTS of functionality anyone barely use or even know. Without that, there's no tooling around this functionality, no adoption. Not even a

Linux (the kernel) has LOTS of functionality anyone barely use or even know. Without that, there's no tooling around this functionality, no adoption. Not even all TCP socket options (setsockopt) are documented! Systemd pushed forward proper usage of capabilities, better watchdogs (in a broader sense, as systemd supports all kinds of them), isolation, policies, and so on and so forth. You need it all to efficiently control the daemons, and it's great when it's all available in a single suite.