Why do we need the 60fps lock

Ok, I understand that to keep the game competitive, 343 had to make halo 5 run at a smooth 60fps, which is totally fine, but of course, sacrifices had to be made, what I don’t understand is that nobody has any option to sacrifice framrate for quality graphics and gameplay, I play on a 55" tv so I notice that the game has zero anti aliasing, and it bothers me badly, I don’t really care about 60fps as long as the game shows fluid motion (30-60) I’m not hating on 343 for creating a near perfect game, but I thought I’d just adress this because it really deducts from my gameplay and overall aspect of enjoying the game because shadows are compete messes
Edit : you can see how long I’ve been on the game too with my beta badge and the fact I’ve already got all of noble team’s armor

As a guy who typically plays on PC, and comes across to the Xbone almost exclusively to play Halo, 60fps smooth is really appreciated. Going back to anything less just feels jarring and icky.