https://en.wikipedia.org/wiki/List_of_NBA_champions
Also, if you look at the 70s, there were “dynasties”. The Knicks made the Finals 3 of 4 years. The Lakers did the same. The Bullets made the Finals 3 of 5 years. And the Celtics won two titles in three years.
What the 70s also had, which we are now missing, is competitive balance.