Using one's skills as bargaining power does not make one a capitalist. That person is still a laborer, their skills are the means of production. Capitalists control the means of production, laborers are the means.
The "labor" vs. "means of production" dichotomy is just as false and pernicious as the "labor" vs. "capital" dichotomy. "Means of production" are capital. That includes skills.
> Capitalists control the means of production
As far as machines in factories go, yes, the owners of the company own those, the workers do not (unless the company is a worker cooperative, those do exist).
As far as skills go, though, no, capitalists do not control those--the people who have the skills do. But they need to realize that their skills represent ownership of capital in order to make the best use of their control over them. Many, if not most, "workers" do not realize this--and hence they are at the mercy of the "capitalists" who do.
> Capitalists control the means of production
As far as machines in factories go, yes, the owners of the company own those, the workers do not (unless the company is a worker cooperative, those do exist).
As far as skills go, though, no, capitalists do not control those--the people who have the skills do. But they need to realize that their skills represent ownership of capital in order to make the best use of their control over them. Many, if not most, "workers" do not realize this--and hence they are at the mercy of the "capitalists" who do.