That's the right perspective to look at it. It wasn't just increased productivity which brought us to HDLs, but it was the sheer impossibility of understanding or keeping track of the ever larger and more complex designs with schematics. With todays software systems we have exactly the same problem (but computer scientists apparently prefer to retry and reinvent things than to study anything old). UML (and with version 2 also SysML) finally had an equivalent textual representation, but it was much too late.