I agree with you that this article attempts to be self-serving, but amusingly I believe it accidentally lays out a case against movie critics.

The author lays out a case by which critics are a barometer for a film’s performance. Reviews can be used to measure a film’s total box office receipts. The problem is that the aggregated critical reviews are just a correlating data set to the actual box office receipts. So, if you are a studio, why would you need the additional measurement if your business is required to measure the correlating figure (box office receipts). In the same way you don’t need two watches to tell the time, you don’t need critics if all they do is tell you what you already know.