Yes, programming languages are designed for a purpose and importantly for a concrete system. Erlang is the way it is because it was designed for Ericsson's phone network. C is the way it is because it was designed for the PDP-11. Logo is the way it is because is was designed for young children. Go is they way it is because it was designed by Google for Googlers.

You can't design an abstractly "perfect" programming language without any context. Which is why the author I think focuses on "perfectable", as in the language can be made perfect for your purpose but it's not going to be one size fits all.