A lot of the criticism I see Hermione and Dumbledore get reminds me of Hannibal Buress’ “Why are you booing me? I’m right!”
Like Hermione being right about Crookshanks and Scabbers, or Dumbledore being right about Voldemort’s defeat and Harry surviving.
Maybe they act like they know better than everyone else because they DO know better. They shouldn’t have to apologize for not being wrong.