The graphics aren't that bad, considering how old it is. Yeah, a modern game would probably look better but good graphics don't make a good game, nor should realism be confused for good graphics.

IIRC Planetside used to at least have totally lopsided battles. They'd mark zones as hot and people could spawn there to even things out, but we used to do large server-wide organized attacks where we bring a large number of troops to capture zones before the enemy could organize a counter. I don't know if this is still true, but the fact it isn't (if it isn't) means there were issues they were trying to solve, which there totally was. How do you suppose a Halo skin would fix the issue, especially if they can't just spawn in there? How do they prevent one team from being rolled (which will be even worse without a third faction to level things out against the one faction doing the rolling)?

I actually prefer the world design of PS2 to Halo Infinite. Most of the world in HI is identical. PS2 at least has a few planets with very different terrain, and they also have regions that are largely different from the rest. The terrain also makes some vehicles more or less useful, which doesn't really happen in HI. In HI every vehicle is essentially exactly as good in all locations.