Gasp reading “capitalist” as someone seeking to exploit something in order to make capital must be hard. There’s no way anyone could have possibly done something similar to that before supply side Jesus handed capitalism to white people in London or whatever.
While the concept as capitalism didn't exist, there are certainly many facets of the ancient economy that are facets of capitalism.
Most of the economy was privately held, just certain facets of modern capitalism like corporations didn't exist.
So, while you are technically true, you know exactly what they are talking about. We can't 100% relate, but issues like laborers getting a fair wage and the rich exploiting the poor were just as relevant then as now.