> What matters is characteristics of the runtime

I'd say what matters is who is your sponsor.

C/C++ had Unix/AT&T and Microsoft as sponsors.

Basic and C# had Microsoft.

Javascript had all browsers' makers.

Java had Sun and Google.

Fortran and Cobol had IBM.

Python, Go and Kotlyn have Google.

Objective-C had Apple. When Apple was in the ropes Objective-C wasn't popular. Then Apple got big and Objective-C got big, also.

Turbo Pascal/Delphi had Borland when Borland was Borland. Now Borland is Embarcadero and the language is fading.

Smalltalk, Lisp and Lua had great runtimes but never had great sponsors.

Ok, there were exceptions: Perl, Ruby, DBase... but some of these are falling behind already.