The problem isnt suppressing people from talking about negative side effects, it's that they need to be suppressed from doing it "like this".
Legally, as an employee of a pharmaceutically company, I am required to report when I hear by any means of a side-effect, defect, or off-label use of one of the products manufactured by my company. The company would prefer these complaints to be filtered by doctors, not come directly from consumers. We need to spend our time investigating "My patient used drug X while taking acetominophen, and experienced heart murmurs." not "I took drug drug X and now my leg hurts real bad. (but I didnt tell you about when I fucked my leg up playing softball last weekend)."
I can easily imagine many people going "My doctor told me it was all the hamburgers I eat causing my heart pain...but I think it's the anti-excema meds I take...Im going to complain on Facebook because people need to know!" Then the company ends up having to investigate a baseless claim, and improper information gets disseminated via the internet because people wil believe anyone that says "Big Pharma doesnt want you to know!"