I don’t know if this article is typical for a socialist. I suspect it is at least common. Anyway, the author has a low opinion of the self-employed. He calls them the “petty bourgeoisie” who “exploit themselves.” Socialists are obsessed with “exploitation,” i.e. victimhood. Socialists ignore entrepreneurship almost entirely.
The initiative, courage, grit, risk-taking, and exercise of thought needed to succeed in self-employment have no place in the author's narrative. The thought needed to decide what products or services will attract customers, the time and expense spent on marketing, getting and satisfying customers, and the riskiness of being self-employed are all ignored.
Suppose SE is an excellent young tradesman (electrician, carpenter, etc.) who works for someone else. His employer pays him a steady income, keeps him busy finding work for him, and provides “fringe” benefits like health insurance and paid vacation. Of course, per a socialist he is only an “exploited wage slave.” Yet SE believes he could do better in the long run by becoming self-employed and maybe in a few years employ others. He knows what his employer charges customers for his work significantly exceed what he gets paid. He might wish to specialize in specific sorts of work or customers. There could be other reasons. In any case, SE would like to “be his own boss.”
If he chooses to do so, then SE will incur the time and expense of finding customers himself and/or pay somebody for this. He might get a few among customers he did work for with his ex-employer; maybe not. He will have to buy his own health insurance and he foregoes paid vacations. If he doesn't have enough savings, he will have to rely on some financial help from others for a while until he attains a steady supply of customers.
This is not to say all who become self-employed do so for the same reason as SE. They may do so while in more desperate circumstances, like being laid off during a tight job market.
All this is totally ignored in the socialist’s narrative Little joy in being your own boss. I have never seen an advocate of socialism acknowledge any worker's choice between (1) a more certain, reliable income as an employee and not having to spend time or money to find their own customers, and (2) an iffy income that comes with being self-employed. And of course, if the time comes when SE employs others and pays them wages, a socialist will regard SE as a “despicable” capitalist “exploiter.”