I think it's more subtle than that. An interesting program usually contains parts that are "easy" (e.g. interfacing with a database) and parts that are "hard" (e.g. complex algorithms). To be productive, you would want to get the easy bits out of the way so you could concentrate on the hard bits.

Making Python or Scala talk to Oracle (for example) is so trivial you can write that bit of your program in no time at all, then get onto the interesting stuff. In Lisp, you have to spend significant time on this trivial stuff. So if you are writing a program on your own PC for your own use, then Lisp is fine. If you are programming anything that is going to run on existing infrastructure or interoperate with other programs, it's very difficult to justify the additional effort of using Lisp.

And I know a bit about this: I wrote Oracle bindings for OCaml! It was fun, sure, but can I justify it when there are already Python bindings? Hmm.