"I was consistently talking about the developers perspective, not the user! "
"If you think editing configure.ac and Makefile.am files is easy to learn, I bow to your brilliance, but myself and many others don't share this experience."
I dont think it's any harder than lots of other things that developers have to do routinely. Certainly in my experience it is much easier than trying to grapple with e.g. RPM packaging.
"Binary tarballs, as you say, are limited/useless"
I didnt say that at all. They are great! But not all distros are compatible. And it's not the developers job to fix the broken distribution.
" (dependency hell, different architectures)"
Different architectures require recompilation, obviously. Make is the best tool for that. Dependency hell? If I understand you correctly that is a package manager problem. It used to drive me nuts years ago trying to get RedHat to work, but I have used Slackware for decades without seeing anything like it.