Halo 2 and 3 had a major re-playability factor with the introduction of a visible ranking system. Something most players continually sought to improve, through playing the game more. Not for armor. Not for perks. Just to improve the number that represented their skill at Halo.
Halo Reach took that away, giving players a playtime-based ranking system rather than a skill-based one. Halo Reach saw a massive drop in players from Halo 3 because of this.
343, deciding that Reach was a good starting point (and not a more successful Halo) decided to reattempt the playtime ranking system again, and even slapped us in the face with a Trueskill that can only be viewed online. As if to say “Yes we know you want to see how good you are, but we’re going to make sure ONLY you see how good you are and no one else”.
And that’s what really grinds my gears.