Varsity and Technical Analysis

I've seen a lot of negative sentiments regarding technical analysis, which makes me think of its efficacy. However, if that is the case, why is TA one of the first modules in Varsity? Everyone here recommends Varsity as a beginner resource, which has a pretty solid TA module.

Apart from this, there have been many successful traders (Paul Jones, John Murphy etc. ) who have written texts on TA.

So my question is, where does the skepticism of TA come from? Is it anecdotal, groupthink, evidence based?

I would love to see evidences supporting / refuting both sides before I delve deeper into TA - I wouldn't wanna study astrology, as many people claim it to be.