Generally speaking, encyclopedias are tertiary sources, so that makes sense (though the line between secondary and tertiary sources is sometimes blurry)... but as you say, there are plenty of topics (a niche programming language under active development primarily by one guy is a good example) where the topic might be notable enough to warrant a Wikipedia article but not widely discussed enough to have a good source other than the primary developer. I understand that "well the guy who made it said it" sounds like an obvious argument, but I also understand that Wikipedia is trying to maintain their role as an encyclopedia first and foremost. I'm not sure what the optimal path is.