A player being casual or having a good rank are two separate things. A player with a great rank may barely touch the game, and vice versa where somebody can play constantly but not necessarily consider themselves good. What ranks are considered good depends on each player's view. When you're rank 300k, 100k seems incredible, when rank 150k, 70k seems impossible and so on. At the same time to call people of any rank a bad player isn't very true because that would imply that their ability to improve is already locked... In a game like osu! it becomes very difficult to classify anybody as "good" or "bad" because of the wide range of difficulties and high number of players. Really it just depends on one's own view as to whether they are good or others are good or bad.
