Because its a free software project you are not paying for and use as a gratis gift from the developers and maintainers of the distro. And those developers and

Because its a free software project you are not paying for and use as a gratis gift from the developers and maintainers of the distro. And those developers and maintainers wanted to use systemd. If, as a user, you disagree with the developers and maintainers of your choice distribution, you picked the wrong distro, and should either find developers and maintainers that align with your views or fork it and become a developer / maintainer yourself if nobody provides for your use case. You cannot bitch on a high horse when not paying a cent for any of this about how the developers and maintainers are doing what they want with their distro. Well, you can, but nothing will ever happen - they already made their choice based on their needs and use cases.