Stiftung Warentest has tested 26 Bluetooth headphones (more reviews here) Only models from 200 euros have "very good" sound. Cheap models can keep up with expensive ones.

Top score of 1.8 is shared by the second-generation Apple AirPods Pro, the Bose QuietComfort Earbuds II and the Sennheiser Momentum True Wireless 3, all of which cost more than 200 euros. So far, the Panasonic B100 and Isy IT-W2000 have not been convincing at all in terms of sound.