Thompson: Why is there this swing to populism in so many countries?

Possibly because politicians are starting to realise that they should represent the 'majority view' of their constituents?

We had it in UK in 2016. The politicians, in the main, were against Brexit. But they hadn't realised that the majority (often the 'silent' majority) had a contrary view.

It needs to be remembered that those who shout the loudest do not, necessarily, represent the majority view.