The APL section seems a little off. I downloaded the latest Dyalog version and the RIDE IDE and it was all very simple to use. Despite having zero APL experience I wrote a pretty nifty program to simulate something in my domain in like 3 lines of code. The keyboard thing is a non-issue as the IDE let's you enter symbols and you quickly start to memorize that you can enter command-key r to enter rho and so forth. I've…
I think it's fair to say that font issues were a significant reason for its decline in the late 80s and 90s (well before good unicode support). Other major factors were spreadsheets, which did many of the things APL was best at with an intuitive graphical interface, and OOP. APL didn't have OOP, so it was for dinosaurs. Structured programming could have had the same effect—mainstream APLs picked up ifs and while loop…
See also https://aplwiki.com/wiki/Array_model.