While it can't be denied that polls were misleading, you actually present no evidence that the reason is the "secret hate vote". There are many possible reasons why there is bias in the polls, such as the kind of person that was reachable by pollsters (sample bias), or the handling of potential voters vs. non-voters. Your assertion that the bias is significantly due to people lying anonymously to pollsters for reasons of social pressure is unsupported in your article.