Well, getting into the question of why Lisps and MLs didn't take off is maybe too big a topic for this thread, but clearly the market didn't feel they were great options and still doesn't. Clojure remains a niche language for example.
I suspect one issue is that Lisp never seemed to be well supported on Windows and never came out of the box on Linux, except perhaps for Guile, but Guile never reached any kind of critical mass despite being promoted by the GNU project. Maybe one reason is the lack of learning materials. Even today, although Guile has an initially pretty and appealing website, clicking "tutorials" reveals a complete lack of interest in growing that community - there is only one single tutorial, which is about how to embed Guile as a scripting language into a C program!
I remember learning Python in the 1990s. The learning materials were excellent. Java was also famous for extensive tutorials and learning materials (they've lost that in recent years, the modern Java docsites are just piles of specifications, but when Java was interested in growth they had it). In the end these things matter more than the exact nature of a runtime or type system.
That's a good point. I never really understood why GNU didn't use more Lisp, as the idea of "C for when performance is needed, Lisp for the rest" sounds great, but if tutorials weren't there that explains it. I learned programming later (~2010) and I remember Python being very easy to learn and install on Windows.
I suspect one issue is that Lisp never seemed to be well supported on Windows and never came out of the box on Linux, except perhaps for Guile, but Guile never reached any kind of critical mass despite being promoted by the GNU project. Maybe one reason is the lack of learning materials. Even today, although Guile has an initially pretty and appealing website, clicking "tutorials" reveals a complete lack of interest in growing that community - there is only one single tutorial, which is about how to embed Guile as a scripting language into a C program!
https://www.gnu.org/software/guile/learn/#tutorials
I remember learning Python in the 1990s. The learning materials were excellent. Java was also famous for extensive tutorials and learning materials (they've lost that in recent years, the modern Java docsites are just piles of specifications, but when Java was interested in growth they had it). In the end these things matter more than the exact nature of a runtime or type system.