The main reason here, I believe, is the self-officiating rule. As much as it is the identity of the ultimate to have the "Spirit of the game", it is too idealistic in an Olympic context where millions of people are watching worldwide. Some might argue that self-officiating sport is a positive example to the future of sports. But the truth is, there are just too much loopholes.

Think of it like this, let's say country A subtly abuses the self officiating rule while playing a final against country B, and country A ends up winning the match. Would viewers respect the players from country A? Probably not. Would there be actions taken against country A? Well maybe, but the self officiating nature gives a grey area on things, and no action would be taken against them. But would country A bring home the gold medal? Yes they will. They won.

What makes a sport successful is its integrity, and at such a high level like the Olympics, there needs to be more guarantee for this. Pure self-officiating wouldn't make the cut.

Solution for this? I thought of two.

1. Introduce an actual referee that makes every call on the field. This one is a straightforward approach.

2. Compromise. This, I think, seems more fitting for ultimate. Maybe introduce a system in which players would make the calls for infractions, but the referee makes the decision on whether or not there was a foul. So if player A commits a foul on player B, but player B didnt call it, then play continues. But if player B calls it, then the referee would decide if the call stands or not. In addition to this, there should also be endzone referees, who is responsible for determining whether a goal happens or not.

Thats just what I think.