I can't help but feel that the context of both these comments are too different to be called a contradiction.

The first statement is merely a criticism of those who would rather make an excuse than a commitment, and explaining to people what they should really have to do to solve their problems.

The second statement is a possible explanation as to why people think the way they do in modern society.

Now if Peterson said he couldn't do anything because of Derridah or Marx you might be on to something, but the way I see it you're just being pedantic.