No doubt, the three point shot and its value in today's game has fundamentally altered the sport. Its actually crazy that it didn't happen to such a large degree sooner. It took awhile to change the mindset of coaches I guess. And then Steph arrived on the scene and shit got crazy. the bump in the mid-90's correlates to when they moved the three point line in to a uniform 22 ft as opposed to the only 22 feet in the corners.
How much value does Steph even have pre-1980? He's certainly a really skilled player and would play in the league, but shooting from 30 ft out at a 42% clip would probably be frowned upon when it counts the same as the shots in the paint. I was too young in the 1980 to really give a shit about basketball theory and analytics (as they were), but I wonder if they had any idea of what it would lead to. Imagine if the NFL said touchdowns from 40+ yards out count for 10 pts, or homeruns greater than 444 ft added +1 additional run to the count.