The first PPI policies were sold in the 60s. I had a credit card with PPI in the 80s and it was not uncommon. No where near as common as in the 90's but there were still lots of PPI policies (mis)sold in the 80s.
Many people were flat out lied to by their banks in order to force them to take out PPI. The banks are now being forced to take responsibility for these lies. Isn't that a good thing?