Swimming is cultural, in most countries especially in Asia there is no swimming culture, you don't need it to survive and there are far more important things to learn about.

Why spend the energy learning something you would never ever do, when there are better things to learn about.

For example, I never learnt to swim, but my parents taught me rice farming, metal work and foraging skills (rural Sri Lanka). There were waterholes all around but you didn't need to swim to enjoy them and the nearest sea was many hours away, so it wasn't needed.

At school we learnt how to identify venomous snakes and basic first aid, what to do if you come across an elephant, a leopard or a sloth bear, which is absolutely essential here. Did you learn those?

People prioritize different things and you cannot generalise billions of people as Shitty parents. It shows your ignorance.