The Airpods aren't overpriced. They are a bargain. The issue here is that you are extremely misinformed and quickly to conclusions.

sound worse

This is only a tiny, tiny, tiny aspect of what makes a good product. The vast majority of people around the world are well pleased with the earbuds that comes with their mobile phones and that's what they use.

When they aren't pleased by them, the best seller is beats.

The reason why is simple.

Sound quality after a certain "quality level" matters shit compared with other factors. Being by far the best wireless devices at that price range, with tremendous build quality, the strongest connection and terrific case and battery life matters much more.

That's why the people that use them, love them.

No wired "in-ears" will come even remotely close to the great experience that is using wireless devices, no matter how good their sound quality is. The sooner you understand this, the better.

For example: The Solo3 provide good sound quality, but nothing that wired headphones at 200$ can't match or surpass. However, their build quality is amazing, they have more than 40h battery life, really great features, the W1 chip means a fantastic pairing process and strongest connection, and that's why almost everyone would prefer them to any other alternative.

Again:

After a certain level, sound quality goes to the back seat. And that level is not higher than the earbuds that come with the iPhone 7 and your typical 320kbps MP3. That is the market.