The issue is that there is no utopia. If you make one, it instantly looks like a cover. "A place of pure light and peace" is hiding something. Even if the DM intended for it to be perfect, the players could certainly see it as a threat. Unless the DM breaks the fourth wall and explicitly tells them it's real, there's no way for the players to know that.

Then, when that place that has tons of resources is fighting some poor faction next door, it looks pretty damning. The same issue as above happens if you portray them as pure evil. There's no way they're actually that evil, and it must be propaganda.

This all happens even more if your players have been trained to spot these things because this is how the real world works.

From OOP:

thats the thing he let us do all the worldbuilding at the outset and then decided that the capitalist u.s./cop city proxy we set up was actually an israel proxy that he was going to commandeer to be The Good Guys.

but it went straight over all our heads lmfao

So apparently he let them design the general layout, which had the authoritarian government and the rebels fighting them, and thought the ‘cop city’ they’d made sounded awesome and heroic and was totally the super-cool state of Israel, and the rebels were those dastardly Palestinians, and ran the campaign that way.

Don’t do religion, kids.

When you're dealing with a setting that is that clear-cut and obvious, you tend to have a situation where the place of light and peace is rotten at the core and has very effective propaganda, while the cartoonish violent rapists are often downtrodden victims whose suffering is made invisible.

Sounds like that would be a pretty bad dungeon master though.