You're acting like I'm wrong, but I'm looking at the top 50 most played Xbox games
here and Halo 5 is 47th. Forty-fucking-Seventh. Like how do 343 look at that and pat themselves on the back like "good job team". You can't even use the "bu-but it doesn't get updates" since you have single-player games like Fallout 4 which doesn't get updates with more players. It's laughable. Don't even get me started on the fact that garbage like BF5 and GoW5 have more players.
Problem is players still buy Halo because they hope and pray that 343 don't fuck up this time, yet they do every time. So instead of looking at retention, people look at the copies sold and go "See, 5 sold the most since Halo 3" (which isn't even an achievement since you're competing with Reach and 4, great job).