People say that if you don't like systemd then don't use it -- and that's what the people who don't like systemd want to do. But not all of them want to compile everything from source like Gentoo.

So use Devuan, you say, or some other esoteric distribution with six thousand users instead of a million. Which is presumably what they are doing.

But they still want Debian/Ubuntu to use something other than systemd by default, because you need a lot of people to use something in order to get good bug reports and get people interested in fixing those bugs and making improvements to it. Use in popular distributions is the only way for the alternative to get those things, which makes people who don't want to use systemd unhappy when the most popular distributions do.