Where else would you take shits? The nice fields where you grow food, or the concrete superhighway covered in pollution, oil slicks and pieces of exhaust chambers and tires?
Cotton is king in hot, dry environments. There’s a reason runners wear cotton shirts in hot weather. Sweat evaporates and keeps you cool, they breathe, they’re light and breezy. Big baggy trousers are GOAT because you can just pull open the top to immediately vent the hot air, whilst protecting you from sun, and the pumping action from hiking circulates cool air on your legs
The best hot weather pants I’ve worn are RailRiders Ecomesh or Damselflies, and they’re literally Jinco tier baggy. The US Army was doing it wrong when they issued you heavy duty close fitted nylon pants