You don't need to have an opinion on everything.
Before the internet, people generally didn't have enough information to form an opinion on most things, so the default answer was "I don't know".
Nowadays people are bombarded with so much information that you have people forming strong opinions on a topic and sometimes even making that opinion their entire identity while barely understanding any of it. I'd much rather have a few strong opinions on a few topics I care about, and leave everyone else to worry about the rest.
Perhaps favourite colors is a little different to deciding on vaccines or climate change, but the sentiment is the same. "I don't know" is a perfectly valid answer, and more people need to get comfortable with it.