Yes and no. The data show that it depends on the context. Sometimes socioeconomic status is problematic, but most of the time, the cause is a feeling of economic hardship. So it's less tied to income as such than to having the impression of not having access to what we feel we are entitled to.
Let's take the United States as an example. I'm going to draw a very important parallel. Many of the people who attacked the Capitol appear to have been upper middle class and not in circumstances that involved a great deal of hardship.
However, most of them felt deprived—deprived of something they felt entitled to, or about to lose their middle-class or upper middle-class privileges.