Putting aside the 2 draws at Ibrox this season, in the 70s, 80s and 90s Rangers and Celtic were in various states of financial crisis and we even had Aberdeen and Dundee Utd win the league (and Hearts blow a title chance when they should have won it).
There was a financial disparity between the clubs, but not nearly as wide as it is now.
As someone who grew up in an era of 70s, 80s & 90s you will have witnessed the restructuring of the leagues, the re-structuring of the prize money and tv money and the restructuring of the gate money from 50/50 to home team keeps everything. All these things were instigated by the OF with the sole intent of making them richer and ensuring the gap between them and the rest of us widened to the extent it would be impossible for us to compete.
The rest of the clubs, including ours, bent over to accommodate them because they were scared the OF would leave the Scottish League.
It happened everywhere of course, from the EPL to the Champions League. All of it designed to keep the rich richer and reduce actual competition.
It could be changed, but nobody in Scotland has the balls to do it. So at least for my lifetime I don't expect we'll be able to offer much competition at Parkhead and Ibrox when they can pay individual players more in a year than our entire salary budget.