Every now and then I see posts like this and yet, the Lisp languages never took off after the 2000s. I understand that there might be some value to learning Lisp, but much of the things that made Lisp attractive before are already available in Python, Java, etc. and I see no "enlightment" in learning Lisp.
This comment is going to get downvoted heavily here, but it's high time every one accepted the fact that the Lisp family is almost dead and move on.
Please take a look at Lisp macros. I finally got it at some point. It is a way of generating code on the fly. After I understood under what circumstances macros can abbreviate code, every other language will look unnecessarily verbose.
This is enabled by the fact that code in Lisp is also written in the form of lists. Code is data, data becomes code if you write a macro to process the data.
For example, is the following data or code?
(book (author "Jonathan swift") (title "A Modest Proposal"))
It definitely looks like data. But it can be made into code using an appropriate macro.
What probably Lisp trails in is type inference and bleeding edge libraries.
SBCL type inference is actually getting better and better over time, giving you pretty effective gradual typing. Additionally, a Common Lisp implementation called SICL is in the works, with an advanced compiler and type inference engine.