Uncritical trust in authority can be problematic for several reasons. First, even if the source of the message is a legitimate, well-intentioned authority, they may not always be correct.
This makes me think of all the activism done by children nowadays. Even though the kids are correct and fighting for something very real and big, they are always doubted just because of their age and lack of authority. This along with fake news has caused a lot of doubt among issues like climate change.