I do not understand if you have actual practical experience with medium-complexity projects with visual languages.
Also, wM have been around for more then 10 years now. I am not using it anymore but I have colleagues who do. The "low hanging fruit" stays unpicked, so maybe it is not so easy to provide the things I listed?
From the end-user perspective, you are likely correct. I was musing with my PL designer hat on. The difficulty is the huge amount of work that has gone into the entire unix way or developing software. That's the seductive local minimum.
Also, wM have been around for more then 10 years now. I am not using it anymore but I have colleagues who do. The "low hanging fruit" stays unpicked, so maybe it is not so easy to provide the things I listed?