Comparing across era's is probably not fair to anyone, either Red or Phil. Red is the real McCoy, and will always be the standard by which "great" coaches are measured. It would be an honor to be compared with him, and I think Phil has come to that point of being honored to be compared, but then I think it becomes less about "who is better" than about celebrating the amazing achievements of two of the game's greats. And Phil definitely is one of the greats, though the only one I'd kick in the knee.
We can do the same (and do do the same) with players: Kobe/MJ is a big one, and the same thing is happening: people are spending less time arguing for who is better, and more appreciating the talent and achievements of the younger player.
It's pointess to compare across the ages; let's just enjoy the game and the greats of this era while we can. It's a great game.