I guess this is the same reason Ai clocks are stuck on ten to two. In case of the clocks it is because ten to twolooks nice on a clock so most images will have it. Ai doesn’t understand how time corresponds to how a clock looks, just that something that looks like a clock has two lines there.
So since most depictions of wine glasses are half full, when you ask for a wine glass it will give you one that is half full. Fill level being somewhat irrelevant as it wasn’t part of the training data
For further clarification, the 3 to 5 in brass notes is because the instruments one vibrate at certain frequencies which are related to the length of the route the air takes through the instrument. The valves, and in case of the trombone the slide, increase the length of the pipe and change the frequency it will vibrate at, changing the tone.
Your lips however can make a lot more notes depending on your ability to control your muscles in your lips.