What the public is thinking is useful for politicians who need to choose which lies to tell during a campaign in order to gather the most votes. Or for a marketing person in need to alter their approach for maximum ROI. That's about it.
If we switch to entrepreneurship for a moment, here's another case where public opinion is of little use: The crowds don't know what they want next. How many people wanted Instagram before it existed? Or Facebook? Amazon? eBay? How many people know that it is critical we switch to streamlined digital medical records?
People know and form opinions based on past events. As a mass they rarely know where to go in order to solve real rather than imagined problems. This is particularly true of uncomfortable long-term planning.
Take the situation we have in the US with Welfare and Social Security. By some accounts these programs might implode in as little as 10 to 20 years. They are the elephants in the room. The federal budget reveals this fact. Yet people are focusing on nonsense every day.
The masses are not talking about this. The surveys indicate nobody thought these issues were important for decades, even today. Yet, reality, if I were a parent guiding my kids, is that this is one of the most important issues. One requiring immediate attention. It is not a matter of opinion, it's a matter of mathematical certainty.
While I agree that those are some of the uses, they're not all of them.
Monitoring public opinion is also quite useful if your interest is in actually effectively delivering truthful infomration to the public. It allows testing and developing methods (or defenses, as necessary).
What's key is not confusing what the public believes with what is actually true.
The dynamics of why the public believes what it does, for both extrinsic (media, propaganda, manipulation) and intrinsic (educational levels, cognitive limits, messaging complexity) is hugely useful to understand. Actually, if you're looking for lower-level problems of governance, generally, I'd spend a considerable amount of time in that corner.
100 people surveyed. 80% of respondents think he has food poisoning.
Peter accepts this and endures several additional weeks of pain.
Peter finally goes to a hospital to get checked out.
He has colon cancer.
Peter dies three weeks later.
What people think has nothing whatsoever to do with reality.
That's what this article is about, what people think, not reality.