[kazinator]

The absence of that is because it would require a substantial global recruitment and relocation effort to get that many Lispers into one organization. It speaks nothing to their ability or inability to co-operate on a project.

The vast majority of all software tech ever invented is unpopular today. If we just pick a tech stack, language, editor, OS or anything from the last 70 years at random, it's almost certainly unpopular. That's our first-order effect that forms the bulk of the rational explanation for why anything is unpopular. By definition, not everything can be popular: popularity is the selection of a very small number of artifacts (almost always chronologically recent) to the exclusion of everything else.

[bordercases]

The challenge to that prior is that there is substantial overlap in the features and capabilities that were in, say Commmon Lisp a long time ago and yet there was a substantial delay in those features being accumulated in other languages with vastly greater adoption to this point (like Java, although that example might be disingenuous since the releases of Java and CLOS were only a year apart...)

Likewise during the last seventy years some languages saw wild uptakes in popularity for some languages much later in their life-cycle. Who would have expected the modern successes of Ruby?