When you throw a nade to kill two enemy.... That when you see two friendly running into the fight and "betrayal" It's like wait.... That wasn't suppose to happen. :( One thing I love about the battlefield series is the servers can either have friendly fire on or off. I really wish Halo series had that.
There are gametypes with friendly fire disabled like Firefight Limited, I recall disabled friendly fire was very common in Halo 4 and CE.
The only issue with it is that it doesn't work correctly when vehicles are involved. It's possible to splatter allies, You can also have your vehicle paralized or destroyed by your ally.
There are also ways to push allies off cliffs using scenery objects. And CE had an exploit with Friendly Fire disabled where one could crashing a Warthog into an ally player trough walls.
However if measures like H4 were a bit more widespread in all Halo's MM, then that would stop the angry kid from TK to steal your sniper. Or people from destroying unoccupied vehicles in the base just to make life difficult. since in H4 and 5 there were certain gametypes that the vehicles only spawned when people teleported them into the map, I think it was in Dominion gametype and Warzone. Hopefully for Infinite and the continued support of MCC 343 adresses betrayals in a way that makes it difficult to exploit them or grief.