I think Mixum is right about teams needing 3pt threats on the court. The 6 time champion Bulls had several 3pt threats, including Kukoc, Steve Kerr, John Paxson, Hodges, and possibly the first one of modern times, Rory Sparrow.
Even in the days before zone was allowed, teams could effectively run a zone by switching fast enough. I also found Celtics and Lakers basketball of the time really boring because both teams played mostly zone.
Even so, back then the teams focused on getting a good 2 point shot almost every play. These days, the game has devolved to drive and kick for a 3pt shot or pass around the perimeter for a 3pt shot.
Mixum's specific point was shooting over zones. I've seen enough games the past several years to see that teams will go zone and often disrupt the other team. They'll run the zone until the offense proves they can shoot over it.
Even if the D isn't playing zone, they can more easily cheat off of a perimeter player who's not a good outside threat.
I mean, inside/outside game is well known to be a good balance.