Why are all the most beautiful flags symbols of oppressive regimes?

Have you noticed that Cuba ’ s flag has the same design as Puerto Rico’s, except that the red and blue colors are reversed?

I challenge you to show me any rivers that run in a straight line!
(Actually, the flag’s designer could have matched the real rivers’ contours.)

Although some flags are beautiful (I like Macedonia’s), most of the really nice ones are a pain in the ass to draw.
Peru’s red-white-red vertical tricolor isn’t the most original design, but you can draw it in your sleep. Arentina’s flag need a 36-arm sun, c’mon!
The South African flag must be a nightmare to make it look good if drawn by hand.
The US flag, no way.

I like Kazakhstan’s flag, but I’d never draw it.

Alright I get to fight some ignorance. Here is a straight river:

In name, at least.