I have been flying the same city pair for 30 years. Cash price is the same or less now. 5 minutes ago I booked this city pair for less cash than I did 30 years ago.
In 1985 flew SYD-SFO (on PanAm) Cash price today is less.
The freq flyer miles & cash surcharges (where applicable) have continued to rise over the time I have been a member of ffp's (1993)