i personally dislike how the term dozen has lost all its context. it was initially a lucas specific thing, from an nctzen's tweet saying "if ten's stage name is ten then lucas should have been called dozen because he dozen sing, dozen rap, dozen dance", or something along the lines of that.
i personally believe that an idol's job isn't limited to singing, dancing, and rapping - even someone pretty who isn't the best at singing, rapping, or dancing may add value to the group by raking in $$$ from brand endorsements, cf deals, etc (which really is where the $$$ is tbh). or maybe said idol is super funny and adds to the group's recognition by being on every variety show at every time of the day.
as long as the entire group isn't made up entirely of unskilled people (musically and dance-wise), nor are the "dozens" dragging the groups' performances down, all's good imo