There’s not just two classes, there working class, middle class, and upperclass, which I suppose you could call the owning class.
Yes the middle class also work, so perhaps a better name for the working class would be the laboring class, the names are not important, but the point is that working-class people tend disproportionately to have blue-collar jobs, and middle class people tend to have white collar jobs. They tend to work shorter hours for more money, and so have more disposable income.
That kind of rhetoric is dangerous. If a white collar worker hears it, they might think they have class interests that oppose those of blue collar workers. And that might convince them to vote for conservatives who promise to oppress the working class and give tax cuts to the rich.
It isn’t rhetoric, it is reality.
If you are not prepared to face fact then you are part of the problem in fact you are pretty much the entirety of the problem.
White collar workers don’t have significant class interests in opposition to blue collar workers. We all benefit from that which benefits the poorest of us. For example, when the minimum wage is raised, we all end up making more money than we did before. It’s not reality.