Open-back headphones occupy a rather specific place in the headphone market. They are rarely the pair you buy for commuting, working in a busy office or taking onto an airplane. Sound leaks out, outside noise gets in, and most of their advantages only become apparent when you have a quiet place to actually listen.
For people who do have that space, however, open-back headphones remain some of the most compelling options for serious listening. Removing the need to acoustically seal the earcups can create a more natural sense of space around instruments and vocals, which is why open-back designs remain so common among audiophile headphones meant for a desk, listening room or private office.