What makes a character likable?
Obviously, everyone has their own preferences, and some archetypes typically attract more fangirls/boys than others, but in one show everyone will probably have one favorite and one… not-favorite, if you will.
Haikyuu!!, on the other hand, makes life very difficult for its viewers by instilling all its characters with an easy, likable charm. Choosing a favorite character thus becomes infinitely more difficult. Everywhere I go I always hear, “Everyone in Haikyuu!! is so likable! I can’t choose a favorite.”