Moreover, this kind of explanation can't be called explanation at all, because the on-site explanations are all non-professionals and don't understand the team's tactics at all. Although everything they say seems to improve the atmosphere of the stadium, their unprofessional or even retarded explanation will only make the scene cooler. A few people are biased towards serious interests, leaving aside the teams they don't like and just saying how to …
NBA commentators are all professionals, either NBA players or coaches, so they have a good grasp of the rapid changes on the field. Even if they have occasional preferences, people will not ignore the role of role-players. Just look at other people's game records: which player played, in which year, which day, when, how many points, how many rebounds, how many assists, how many blocks ... all have detailed records. Most importantly, the NBA is not a "yamen". Commentators can play freely, without too many restrictions, and they will not worry about offending people and fans, and whether superiors will give you little shoes to wear ... In China, fans' preferences can often affect the commentary and even the referee's penalty, so how much pressure do you think the commentary is? Dare not say anything, can only shout slogans: Come on, defend, and so on.
There is also the interaction of fans. The interaction of domestic commentators gives fans a sense of pressure that they have to say: they can't win if they don't say it, and the players don't work hard. However, in the NBA, fans voluntarily interact and spontaneously activate the atmosphere of the stadium. Even without a commentator, they can understand the game. After all, most of them are experienced fans (especially Staples and Madison Square Garden in new york).
Finally, NBA commentators are employed by various TV stations. Their popularity determines that they can ignore the company's requirements, mainly because fans like them, so they will not lose their jobs. Even if you lose your job, the coach can copy it again.