What does an NBA team gain from winning the championship?
Is the team worth more, or do they get more revenue specifically for the owners?
Teams that win the NBA championship primarily get increased ticket sales in several ways:
There is no "prize" from the league, however. The franchise value likely goes up, but there's no direct connection there - it's based on the assumption of the above. Per Forbes, the value of the Warriors has increased dramatically since their first championship - although all teams have increased significantly, the Warriors' increase was significantly more than other teams over a similar time period (the Warriors are about 10x as valuable now as in 2013, while the Knicks are about 5x, the Bulls are about 4.5x, etc.).