The problem with that would be that it would make switching to another linux ditribution very, very easy. They would have 99.99% compatibility so a lot of people would switch to another distro if they add stuff like recall.
They would also be opening the can of worms that is massive software support for linux (which is arguably already opening.)
see systemd.unit(5), systemd.service(5), systemd.socket(5), systemd.device(5), systemd.mount(5), systemd.automount(5), systemd.swap(5), systemd.target(5), systemd.path(5), systemd.timer(5), systemd.slice(5), systemd.scope(5) systemd.link(5), systemd.netdev(5), systemd.network(5) and honorable mentions podman-systemd.unit .container, .volume, .network(…again), .kube, .image, .build and .pod