Encyclopedia britannica:

political program or movement that champions, or claims to champion, the common person, usually by favourable contrast with a real or perceived elite or establishment. Populism usually combines elements of the left and the right, opposing large business and financial interests but also frequently being hostile to established liberal, socialist, and labour parties.

Wikipedia asserts a similar definition

History.com again corroborates this:

The style of politics that claims to speak for ordinary people and often stirs up distrust has risen up on both sides of the political spectrum throughout U.S. history.

Your definition is objectively not what the general populace means when they say 'populism'.