Since people are selfish, I'll mention two reasons why booing actually negatively impacts YOU, the fan.

1) Having people cheer and support you makes you play dramatically better. Having people root against you makes you play dramatically worse. It's the entire principle behind home court advantage, which is absolutely a very real thing.

Booing your own players or team causes them to play worse, simple as that. Why would you want that?

Even established veterans struggle to perform when Portland fans turn on them and make them the heal. Jamaal Crawford has been a legitimately quality player everywhere in the NBA, except Portland. Raymond Felton is a highly valued member of the Thunder and the Clippers and Knicks before that.

2) Booing doesn't just reach the player you don't like, it negatively impacts the whole team. Players don't want to play for teams where they feel fans mistreat them, or their teammates. When a player like Nurkic has to watch his teammate and I assume friend be publically eviserated, you don't think that effects how he feels about resigning at the end of the season?

So much is made about Portland beeing a place that can't attract free agents. Well Portland fans, you play a role in that.

Those are two of the less obvious reasons. We all know that booing a player can emotionally scar them, just as it would if someone booed you every day at work, no matter how hard you tried. Look at Greg Oden. When he was drafted, everyone talked about how wonderful a person he was, and I remember a few hilarious and relatable commercials he made early on. The weight of expectations and the pain of his own fans turning on him were primary causes for why his entire life spiraled downwards into depression and alcoholism.

人们欢呼吸毒者, rapists, drunk drivers, wife abusers and worse. Booing a good person who obviously cares and tries hard makes you a total douche (and don't think they don't see what you write about them online and on social media as well).