Its hard to give you something concrete. The topics you gave as examples are vast. For my own purposes I add feeds to my rss reader based on what I come across by reading other articles in my reader.
Maybe checkout some communities about the topics you are interested. Lemmy has for example a large and enthusiastic Linux community. Brodie Robertson also covers a lot of different Linux topics. You can also take a look at recordings of developer conferences. The people that give talks often write a blog as well.
The choice of init system is up to the distro maintainers because init scripts are usually created and maintained by the packager of a given application. Debian for example chose its init system via a democratic vote. Distros that focus on different init systems exist, like the Debian fork Devuan.