An average quality headphones are in the price range of bluetooth headphones. So I don't understand your point. I couldn't find anything below 10€ with decent

An average quality headphones are in the price range of bluetooth headphones. So I don't understand your point. I couldn't find anything below 10€ with decent sound quality, and it was hard to find something at that price that was good. Moreover, they lasted around 3-6 months for me, while a 25€ Bluetooth headset I bought 3 years ago is still working and the sound is better.