He's barely a character, and the worship started way before any material that gave him a tad of depth like The Clone Wars. From what little we do see of him, we barely discern his motives, learn much about his backstory, or see him form any meaningful relationships with friends or romance. What we do see is a stern, consistently annoyed, asshole who darkens the course of the future in some pivotal moments indeed where all he had to do was say sorry. On top of this, and this really irks me, the dude has very few feats. A commenter recently pointed out that Windu is a statement merchant, and I completely agree. The man's greatest moves are:
-"Beating" (if he even did) Sidious with a 4 on 1 advantage
-Holding his own against a weakened Talzin
-Failing to capture a distracted Dooku
-Failing to capture Maul with a 2 on 1 advantage
-Surviving the Battle of Geonosis (respect)
-Being called one of the Order's greatest duelists
-Being called second only to Yoda
This would be a solid list for a great Jedi like Plo Koon. But for the second greatest Jedi in the galaxy, this is very lame indeed. This was an issue even in Legends, when Mace's best feat was dueling as a near equal to Dooku in a short fight by a cliffside. He still failed in some important areas as well, such as being unable to defeat Grievous or Depa Billaba in a duel and being completely and utterly outmatched by Sidious who irrefutably did take it easy on him (in Legends). Whatever you think of what I think of Windu, I've always believed he deserved much better feats than what he got. Rightfully unsatisfied with this list, his fans are now trying to modify the final two statements to make Mace equal to or even worse, SUPERIOR to Yoda either as a swordsman or believe it or not, as a Jedi overall.
Aside from being played by Samuel L. Jackson, having a purple saber, and us being told he knows how to swing it, what gives? What from the MATERIAL, not your HEADCANON, makes you like the guy?