At first glance, there are many things going on in halo 5 that you are not appreciating.
Let's keep this civil, I haven't seen every single FPS played through and through and I doubt you have either. So I might get some things wrong so feel free to connect me.
halo 5 is a next gen game that has huge scale levels and vast playable angles. As evidenced in the gameplay video the game has long range from distance, from being vertical, from being on the ground, inside complexes to outside vistas without loading screens. This isn't as evident in Halo 4 as it is in Halo 1-3 (h4 levels are small and have loading screens).
This type of gameplay is also evident in games like BF3 and BF4, Destiny and Titanfall. This means you see more players fighting on huge play areas. This also explains why games like this are often extremely taxing on hardware. Most other games cited often do not have this level of scope or scale, and are extremely linear and level based.
Once you can get a game with comparable size and scope you see how many games buckle. Either 30fps is involved or resolution is downgraded. Something has to give to push so many objects onto the screen battling at once.
SW:BF levels are small in comparison. And use photogrammetry for their textures. I don't see how that's particularly fair to suggest Halo looks bad when it's clear they are aiming for stylized graphics.