I don't know what people are used to these days, but looking at the diagram in the post, if this is what author calls a DSL, then they haven't seen a DSL in their life before. What I see in the image is bog standard use of procedures to abstract code away. Does the word "DSL" these days mean "use functions"?
It would be a sad day indeed. There's nothing better than an occasional example from decades ago for one to re-evaluate current hype levels in programming ;).
An actual DSL looks like this:
https://www.irif.fr/~jch/software/cl-yacc/cl-yacc.html
(scroll down to "define-parser")
It enables domain-specific abstractions in code. It's not about just naming your functions right.