Why do you think Japaneses have shit taste in anime?
If you don't, skip this as you are correct.
Their lifestyles, cultures, daily life, experience back in high school, etc are much closer to the authors than you. They are better at judging which is good and which is shit.
Otaku have very limited experience with the medium. They don't know much about storytelling techniques, animation or art. Their judgment is very biased and ignorant because most of them watch anime for cute girls and escapism.
>/a/ are not
Unless you refers to /a/ as otaku that is still not entirely correct
/a/ doesn't want to be weeaboo so they pretend to hate Japan
Just because it relates to them more doesn't make it any less shit.
Cuz they didn't like Nichijou.
Because they are a literal hivemind that buy popular things because they are popular regardless of the quality of the work or other works.