Thanks for the info
I abandoned my quest not too long after I posted my rant. I figured the incremental gain of compiling FFmpeg with that library was not worth the effort. Compiling is definitely a viable barrier to entry for noobs like me who don't really know how computer software really works haha.
So just happily converting my videos using the basic build. I suppose this detour in video editing/formatting was just a distraction from my earlier project of cataloging the collection.