Sure, you can swap the relative importance of those factors if you like. My point is that an expert's concept of "quality" is not indicative of market success

Sure, you can swap the relative importance of those factors if you like. My point is that an expert's concept of "quality" is not indicative of market success -- in programming languages, or any other. The 25 best-selling albums of the year are probably not the 25 best musicians, either. But I'll try to answer anyway: Go. Dart. Maybe Rust (depending on whether nonprofits count). Delphi. All of these are in the TIOBE top 25 today. Furthermore, languages like Kotlin, Swift, and C# became a primary interface to their respective platforms, but didn't necessarily start out that way. They got popular, and then became first-class platform citizens. It may have been the plan for them to eventually become that from the start, but I would claim they would have become popular even without the platform. So I put them in the first group. You can write Windows programs in C# today, and many developers do, but I bet even more are using it for web development. And in a popularity contest (Zipf's Law), losing even half of your fans won't change your list position much.