It’s just a demand for something better than A.
In a political tussle between issues A & B, the defeat of A doesn’t mean the public supports B. It just means they don’t support A.
Couple of examples…
Communism vs Capitalism
The people’s revolutions just said they didn’t want Communism anymore. Not that they wanted Capitalism.
Despite what every politician in the West may tell you, the people in Eastern Europe & Russia didn’t choose Capitalism. They chose to be free of Communist dictatorships. And to try another politico-economic order. It’d be a stretch to say they chose Capitalism, given a majority of them hadn’t experienced it for multiple generations
Globalisation vs Isolationism
People are saying no to rampant Globalisation, not yes to Isolationism.
Whether it’s Brexit, rise of Trump & Sanders, or the anti-trade, anti-bigCo, and anti-globalisation trends in polls, the voice is clear – a large portion of Western populations have grown vary and sceptical of Globalisation. In free trade, free movement of people, and even in free movement of ideas.
What it doesn’t indicate is that the people want to be isolated from everyone else in the world. What it may indicate is that the people want a control on the mingling – to not be completely overrun, without recourse, in their own backyard.
In most cases, people know exactly what they don’t want. And that’s why they voted as they did.
They’re not as clear on what they do want. They just want something better.
This, however, doesn’t imply that they want the only presented alternative. In most cases, they may want another, not-yet-visible solution. One that isn’t currently offered to them. One that even they may not be able to clearly describe/explain, at the moment.