If you play the old Halos 1-3 and Halo 5 side by side, you'll notice two very distinctive differences.
One is map flow: you can go from anywhere to anywhere on Halo 5 compared to how there was a route you had to take or learn a skill jump to get to places.
Second one is pacing: it feels completely off when playing, well actually any game mode now. You can't predict whatsoever your teammates movement, let alone an enemy that is running/walking/clambering around the map. Now it just revolves around this chaotic game style with horrible mechanics added.
When I see CoD gameplay footage, every confrontation ends in someone dying. The extremely low TTK and sprint with fast gun centering work perfectly together. On the other hand Halo 5 has higher TTK which results in a lot more escapes and close calls, and that is completely fine, Halo has always this style of gameplay. What bugs me to no end is that if I now choose to chase someone, I have to do it completely unarmed. And more often than not, I'll just run into some other guy that can easily kill me because of my half shield that I chose not to recharge. What used to be so exiting about Halo was that you could always attack and defend while moving as the same speed as your enemy. There was no choosing between a good place to run or not. It was always about the player's skill.
Again, Halo 5 is not a bad game, but it should have been a spinoff, just like reach and odst. In a spinoff they can try any game mechanic they like because nothing specific is expected from them. What we like is a Halo that actually plays and feels like the old games did, because people expect the main games to at least play the same to some degree.
Inb4 Stop playing then, Mcc exists go play it, don't use sprint if you don't like it, sprint is here 2 stay, but it says Halo in the title!