Seeing more projects omitting installation instructions for debian/ubuntu.

I know there are ways to install software outside of aptitude on debian/ubuntu, (add repo, or build, or download binary, or possibly flatpak/snap/etc).

But being able to download *.deb files was one of the nicest aspect of using a debian based distros and now I'm seeing more and more projects include all distros except deb files.

Someone correct me but I vaguely recall that distributing debs is no longer recommended by debian itself?

1. Am I wrong, and have I only co-incidentally stumbled on projects that don't distribute debs?
2. I am right and this seems like a mis-step, removing one of the most beginner friendly features that helped propagate debian based distros?

Flamesuit on.