It was so much worse before 61131. My career in industrial automation was on PLCs that predate 61131's existence and had no structured text language of any kind. Ladder only. I helped write a toolchain that compiles languages similar to 61131 (but, again, predating it) down to ladder. I've seen an implementation of bitwise floating-point math in ladder that no mortal human could possibly understand.
Our experience was not that companies think electricians are stupid, but that they're electricians: they know electrical stuff, not computer programming. A ladder diagram is immediately recognizable to an electrician or technician who needs to diagnose an equipment failure and wasn't involved in writing the program.