I would like to say that the Sixers gave a cavalier effort but that is just part of the story.
You see I don't believe it is an effort problem with this basketball team. For one I think they get out-coached and have since Larry Brown left town. And Eddie Jordan and Mo Cheeks are not horrible coaches but they are one trick ponies. They do not appear to be able to build a plan around the talent and the personnel.
Now ironically Larry Brown is also like that but he has the clout and the whining /temper tantrum abilities to make his boss get the personnel to match his system. He also believes in defense.

Hey welcome home Allen. And boy was it nice to see a packed house!