If one of your two best players isn't a natural facilitator, the team is going to struggle unless it has immense talent.
Paul George + Kawhi, and Jayson Tatum + Jaylen Brown aren't that different in terms of the problem the pairing has. They kinda overlap. It's always better when your two best players impact the game in different ways rather than being clones of one another.
This is why LeBron and AD are tough to deal with. LeBron is a GOAT-tier facilitator and scorer. AD arguably the best defender in the league, a great rebounder, and can also score with the best of them. Together, they cover pretty much every aspect of the court on both offense and defense.
KD and Curry didn't overlap either. Both willing facilitators, KD a long and athletic and versatile defender who is unguardable regardless of coverage, GOAT tier scorer. Curry the GOAT shooter and his natural range being at the 3 point arc complimented KD's being mid range.
Neither did MJ and Scottie. Scottie a GOAT tier perimeter defender and facilitator. MJ is MJ.
Shaq and Kobe. Neither were pass first guys but their games just meshed together perfectly. The pattern to me is obvious.
Teams need to stop pairing clones together. It doesn't work.