Why is populism suddenly all the rage?

In 1998, about 300 Guardian articles mentioned populism. In 2016, 2,000 did. What happened?
" Revealed: how populists tripled their vote over 20 years

Populism is sexy. Particularly since 2016 - the year of the Brexit referendum and the election of Donald Trump - it seems as if journalists just cannot get enough of it. In 1998, the Guardian published about 300 articles that included the terms "populism" or "populist". In 2015, these terms were used in about 1,000 articles, and one year later this number had doubled to almost 2,000.

The increasing popularity of the term is no coincidence. Populist parties have tripled their vote in Europe over the past 20 years. They are in government in 11 European countries. More than a quarter of Europeans voted populist in their last elections.