If you’re in a boat in a river, your “natural” speed is the speed of the river. Same with air.
You point about a sailboat and wind is confused; the pressure comes from the fact that the boat is traveling at one speed through the water and at a different speed through the air.
You point about a sailboat and wind is confused; the pressure comes from the fact that the boat is traveling at one speed through the water and at a different speed through the air.