Yes. Questioning the hegemony of text as an I/O format is a more viable thought experiment than questioning maths.
Interestingly, putting the start of the downturn in the 80s (I'd agree) links to the rise of personal computing, and the broadening of the user base(widening of the problem-space) w/ generalised use of text encoding...
causality? Correlation? time coincidence? one of the pinch points in CS history that further narrowed our conception of 'computers'