Being able to stand on top of your friends and tbag their head is an integral part of halo gameplay and you all know it. And it’s very important for custom games, like jenga or tetris and so on. I also don’t feel being able to ignore your allies is in the spirit of halo either.
I read the title and my first thought was “no why would you want all those annoying people running into you all the time” then I read the post and your right we need player collision.
I think it’s just a technical thing currently. It’ll definitely come with the full game. I’d put money on it.