The question seems clear.

The functionality this user is concerned with is 4 posts above. It is USB audio for the Teensy 4, a model getting plenty of press in "maker circles" about its speed and capability, but little information about the fact that it is still a work in progress.

Desiring a warning about work in progress regarding functionality common to the product family is not unreasonable. Being annoyed that a purchase was ... premature is not unreasonable.