Of course its different since those players were all acquired in the draft or through trade, not some kind of collusion that allegedly began at the 2008 Olympics when all 3 were under contract to different teams.
Whether him leaving the cavs makes him a coward is just a matter of opinion. If he went to NY or any other team that could've gave him max, people would say he didn't pick Heats beacuse they couldn't pay him max and therefore, he is greedy. If he stayed in Cleveland, which many people believed he would up until last night, people were already saying that his ego is too big to allow him to go to Miami and play on "Wade's team". If we over read too much into it, it really doesn't matter what his decision is as there is a negative spin on any team he chooses.
At the very least, the Cavs fans now know that his decision is based on winning as he will get less money and have to somewhat put his ego aside as it is Wade's team and there is a 3rd star in Bosh. I think its better than to see him leave thinking he went for money or fame at a team such as NY.