In my experience this shape gets uncomfortable quickly because it’s jammed deep into people’s ear canals without accounting for the unique shape of each individual’s canal, so there can be a lot of uncomfortable pressure and friction. Ear buds tend to not go deep into the canal and rest closer to the entrance, making them sustain longer before discomfort arises in the ear.

Also this form factor doesn’t attenuate all frequencies evenly, which can make listening to music less enjoyable.