Well, I would certainly not be an old curmugeon talking about how good it was, but deregulation happened in 1978 which was 33 years after my first commercial flying experience and we've had 30 years since then . . .
Seriously, the problem from the beginning, going back to the Civil Aeronautics ACT of 1938, was how to provide reliable air service in a manner that was economically feasible for the airlines to provide while meeting the "public convenience and necessity" of supplying reliable air service throughout the nation. The system was based on a process of granting air routes and setting fares according to the requests of the carriers, the requests and interests of the communities to be served, and within the judgement of the Civil Aeronautics Board that heard and adjudicated requests in route cases that could run on for years. Typically the result was service granted to two or three carriers in each point-to-point or route line market with fares set, as with utility regulation, to guarantee that carriers would not undercut each other to the point of bankruptcy while still providing reasonable fares to the public. One result is that competetive advantage could only be gained in the areas of service, ameneties, and image. Another result is that union structures and lack of cost competition tended to result in high pay scales and desireable working conditions for professional employees such as pilots, mechanics, and FA's (then stewardesses), not to ignore other functions in the company.
I don't think some of the short skirt, glamour-girl, "resort" atmosphere aspects of flying in the 60's were so much an artifact of regulation as of the times. Certainly airline travel in the 40's and 50's did not have that atmosphere. It is also true that there is a huge difference today in terms of population growth, speed of communications, globalization of business, and the cost effectiveness of the modern jet liner which hugely affect the travel atmosphere today, deregulation aside.
OK, the curmudgeon part is that, yes fares were high then, and yes travel today can be hell, or not, lots of times. Personally I think the opportunity we have to move around the world with ease, and at a low price is fantastic. Maybe the system just needs a little adjusting for comfort, if some way can be found to do so.