The biggest factor in this series, to me, was Kobe Bryant's absolute consistency. He got over 30 every time except when he was doubled consistently. Then he got all sorts of assists. When the Lakers lost two games, Bryant got in everybody's face about defense.
The last time the Suns got in the Finals, in 1993, the lost to a team with Phil Jackson as coach, and there was this superstar on that team, who produced a Bryant-like performance. His name was, I believe, Jordan.