The point is I don't want to install pkg-config. I know exactly where say libcurl is, as I of course build and install that from source. If there is another dependency I would do the same. At least with makefiles I could also just edit them easily myself quickly. Autotools already makes that a longer cycle to fix when things go wrong. What does it hurt to at least give the option for me to tell it exactly where to get the library it wants to link to? Put in the README/INSTALL the version dependencies (though the library itself should offer some way to check this, and let it abort if it is a bad version).
What is wrong with leaving in the manual override option? What is crappy about leaving people the option to not install more abstraction layers on things they don't want? If I want enough abstraction layers I may as well just go use windows and autoupdates.
Correct me if I'm wrong but it sounds like you're saying it should have two sources of that information rather than one ...
i.e. some extra copy of the configuration information that will of course be unreliable due to it being exactly that ...
If you have been building software since the VAX days (as I have also ... actually PDP11, but I digress)
then you should also realise that if that is what you are asking then you shouldn't be asking it ...