There are mainly 2 types of "college is a scam" people. Type 1 is anti-education and places more value on what they typically refer to as "common sense" and think that you don't need an education to know about something. They're the type most likely to think they know more than experts and argue with engineers about bridges. Type 2 is more anti-capitalist and doesn't view education as a scam itself but rather how costly that education is and the opportunities provided to educated people who paid the price is what they see as a scam. They're usually capable of recognizing and acknowledging their lack of understanding about a topic and listen to experts because they do value education, they just think access to it should be easier and cheaper and provide more tangible results for the effort put into obtaining it. This post is probably talking about type 1.