Did you actually watch basketball back then?
Let's go by decade:
60's - There were a handful of teams in the League and the sport was getting the third and fourth tier athletes after football and baseball. There were teams with 6'6 centers. The fact that the Celtics could so completely dominate the sport shows it was not that good.
70's - A drug induced mess of a decade from a basketball standpoint. A small talent pool was further diluted by the ABA. Stars were one way players like George Gervin. The NBA Finals were put on tape delay and shown at 11:30 for a reason. The product sucked.
80's - While Bird and Johnson saved the game, it took Stern about 3-4 years to clean up the drug problem. Some of the 70's stars like Kareem, Moses and Dr. J really shined in the 80's. The problem was that a lot of teams didn't play defense. The Denver Nuggets were one of the best teams in the West in the 80's and they literally played no defense at all. If you can find a Dominique Hawks game on classic sports, I recommend you watch it. Dominique will frequently be walking back on defense. Kelly Tripuka once said he would never try to rebound again after spraining his ankle going up for a board.
90's - Expansion diluted the product, and Knicks' Wrestle Ball was brutal to watch. Teams couldn't shoot back then either. Weird rules like Illegal Defense created an awkward game, and there were some strange teams pre-analytics (Knicks with 3 guards, Rivers, Starks, Anthony, that couldn't shoot). Europeans showed up in force and the quality of play improved as the decade progressed.
With the end of the 90's, basketball started to get really good. Euro ball and zone defenses had a really positive effect on the game. The influx of talented foreigners like Duncan, Parker, Ming and Nowitski raised the overall talent level. Coaching got better overall, and the game improved a lot.
We are in the Golden Age of basketball. Enjoy it.
