That was the worst thing Carter did.
I was a tot, but I flew in the 1960's and early 70's quite often - even transatlantic in 1969. Back then, people dressed up to go to the airport and we could only ever afford the vastly cheaper red-eye flights out of LAX (I think I was 15 before I even knew that commercial airlines flew during daylight hours). You're quite right, prices were fixed, as were gate times, schedules, etc. I remember my aunts and uncles talking about which airline they preferred and it was always a discussion of how good the food was and if they'd ever lost a bag. In those days, the only thing an airline could compete against another airline with was level of service. Those days are gone. The airlines are in a losing proposition. They've cut everything they can possibly cut - service, free bags, free champagne (yes even for coach), meals, flight crew pensions, pay and perks, mechanics, deep cycles to China, new aircraft orders, you name it - they've slashed it. It's amazing to me that anyone wants to be in that business anymore.