This is not entirely true though. Beliefs and opinions are heavily influenced by a lot of factors. Even educated people are not free from such errors. Like the backfire effect (Nyhan and Reifler (2010)): situations where people become more entrenched in their views when confronted with contradictory evidence.
Other studies have found that when presented with data, individuals with more education can sometimes be more divided in their beliefs, particularly when the topic is politically charged. For instance, some educated individuals may use their knowledge to selectively interpret data in ways that support their pre-existing views, a phenomenon known as “motivated reasoning.” Confirmation bias relates to that. This has been observed in areas like climate change, where political and ideological factors heavily influence opinions. (See for example: https://doi.org/10.1073/pnas.1704882114 )
In other words, no matter how educated or smart you are, you can still fall into ignorance and stubbornness. The key is to train your ability to think critically—especially when it comes to your own beliefs and opinions. Doing so can help you become more aware of biases and avoid common pitfalls in cognitive decision-making.