While I'm not sure I like this editorial in every particular, I do like its final challenge to the capitalists in its audience: telling them that if they want to stop socialism from continuing to gain ground, they will have to address the problems we're seeing with inequality and a lack of economic mobility
Of course, I'm quite certain that the various people I argue about welfare and regulations with would argue that they are trying to address the problems in our current economy, but that the liberals in our government insist on meddling and ruining their efforts. Or something like that.
Largely, though, when I get into those arguments, I tend to get either a lot of talk about countries like Venezuela that are used as examples of socialism's failures, or a lot of details about how more of what we're already doing will make everything better. Neither is particularly convincing as an answer to the difficulties we currently face.
The former, of course, isn't an answer at all. It suggests that one specific set of ideas applied a certain way won't solve the problem either, at best. It neither proposes a solution of its own nor is it sufficient to prove that any of that set of ideas can never work, regardless of the extent to which they are applied or moderated by free market ideas.
The latter is more of an attempt to solve the problem, but it doesn't take into account that our current moves towards less regulation and taxes haven't done much. Nor does it take into account the simple fact that such measures haven't always been necessary in order for us to see growth and improvement; there have been times in the past when we've been better off despite not following all of the ideas that are currently being demanded in the name of growth.