>>111292785If I had to guess, it's because actual security people dressed in authoritarian uniforms gives off a vibe that Disney is trying to avoid. The parks open onto the idealized Main Street USA, the kind of small town where people would leave their doors unlocked and the two local cops were Andy Griffith and Barney Fife. Rather than making people feel safe as you might expect, having a conspicuous amount of uniformed security unconsciously puts people on guard and makes them wonder what could happen at any moment that so many of them are necessary.
Also, without dipping too far into /pol/ territory, as Disney attempts to cater to an increasingly larger audience, more lower class people who think nothing of publicly beating women end up in the park, where they wouldn't have before. Whether we like it or not, the practical end result of encouraging things like diversity and inclusion, is that people with differing opinions about how to act in public or which rules should be followed get included as well.
P.S. The guy in the hat who subdues the main troublemaker and then fades back into the crowd may very well have been an undercover security guard. Watch how he moves.