PHILADELPHIA — Had the Sixers cared enough to punch back for a Game 4 victory, you could maybe have seen a world in which the environment in their home building prepared them for the daunting task of going back to New York for a Game 5. The only difference would've been the logo on the court. That's how well traveled the Knicks faithful were in this game. And, really, in Game 3, back when the Sixers had some pride left to play for. The Sixers were in enemy territory no matter where they played this series. At roughly 1 p.m., Eastern time, on Sunday, as I pulled into the parking lot at Xfinity Mobile Arena, folks in dark blue and orange outnumbered folks in Sixers colors by what felt like five-to-one. By game time, that was closer to eight-to-one. An elated Joel Embiid begged Sixers fans to show up for this series in the minutes after Philadelphia's historic upset of the Boston Celtics. It's somewhat hard to believe that Philadelphia was floating on that euphoria just a week ago.…