We know that the NBA is very meticulous when it comes to protocol. They always do things with purpose and thought and their rules are never without reason.
While the league isn't quick to tell players what they can and cannot do, there are some items that they have been banned completely by NBA executives. It's a list of items that the league deems either hazardous, offensive or unprofessional
Things like the straws, do-rags, chains, and ninja-style headbands were labeled as safety hazards by the NBA while the personalized bandaid, hair logos, and Supreme gear seem to be against the league's protocol of "having any name or identifications" on game-worn gear.
The "big balls" dance and upside-down logo seem to be thought of as offensive by the league.
As for the throwback jerseys off the court, that was an attempt by the previous NBA commissioner David Stren to enforce a tighter, stricter dress code. It's supposed to support a more professional look for players.
Obviously, not everyone agrees with these bans but I wouldn't hold out hope that they'll be allowed any time soon. The NBA has an obligation, after all, to ensure the safety of its players and promote its brand in a positive way.
How they choose to do that is their own prerogative.