My counterargument is when rails came out PHP was just as capable of letting you knock stuff up quickly and meeting the business goals for a startup.
Where rails excels I think is at shops that need to pump out different websites for different clients so that continually starting over cost is minimised.
Rails, like all opinionated frameworks, gives you a great head start for a new project, as long as you follow the prescribed project structure. (It starts to feel worse as you grow and hit the restrictions of the baked-in assumptions.)
Lisp is not "old tech"; Lisp is timeless tech. Like, well, math. BTW, Unix is also rather old, but still does remarkably well, and gave a distinct edge to its users since ~1990s when Linux and FreeBSD became viable server platforms.
Where rails excels I think is at shops that need to pump out different websites for different clients so that continually starting over cost is minimised.
And Lisp is old tech.