The "positionless" basketball Ainge and the Celts were talking about, when they signed Hayward and added Tatum, failed because of the new freedom of movement rule.
This season the big men of the NBA are relevant again.
You can't play the bigs as physical like in previous seasons.
One example positionless basketball is putting a smaller player on a big man.
Before this season, you could push, grab, and hold opposing bigs.
That allowed smaller defenders to neutralize the bigs.
This season you can't do that.
That's why bigs are starting to dominate the league again.
Ainge and the Celts need to adjust and upgrade this Celtics team.
Playing small all the time is just not good enough in today's NBA.