I think it's a lot of fuss over nothing.
The team with the most talented players doesn't always win.
2013 Lakers - many people thought they were practically a lock to be in the Finals and face the Heat, yet they barely made the playoffs.
2004 Lakers with Shaq, Kobe, Malone, and Payton. A lot of people thought they'd challenge the 72 win mark and sweep the playoffs.
2002 Bucks. Coming off a 7 game ECF battle, added All-Star Anthony Mason to their trio of All-Stars (well to be fair Cassell wasn't an All-Star yet, but putting up All-Star level numbers). Pretty much a shoe in to go to the Finals in the weak East. Didn't even make the playoffs.
2001 Blazers. Coming off a game 7 WCF collapse, traded away no rotation players to add All-Stars Shawn Kemp and Dale Davis. Many believed they were a serious contender to the title.
2002, 2004, 2006 Team USA men's basketball teams. (Plus all the other gold medal winning teams since 2000 have had several single digit wins even though they have 10x the individual talent).
Barkley joining up with Olajuwon and Drexler?
Pippen joining up with Olajuwon and Barkley?
Pretty much every Coach K or Calipari team that doesn't win the NCAA title.
Every one of those teams (except maybe the Drexler/Barkley/Olajuwon team and the NCAA teams) ended up imploding.
Even this current superstar Heat team has had great 7 game battles with San Antonio, Boston, and Indiana, and lost in 6 games to the Mavs, and may lose to the Spurs again this year.
This won't ruin the NBA. Besides everybody likes cheering against Goliath.
There's only one ball. How effective is Carmelo Anthony going to be getting 1/4 the shots he get's now? Will the Heat offense be that much more effective? Probably not as he'll just be taking shots away from LeBron, Wade, and Bosh. There defense on the other hand will probably get worse. While a favorite to win, that team will still be beatable.