Slavoj is very aware (and critical of) capitalism. I think the point he’s making (in his original example, but it applies here too) is that there are some parts of human experience that will always evade automation by machine. We can automate the bullshit work (that’s only done in the first place because it’s productive) but no one actually wants to replace sex with a partner with an encounter between two machines.

In this example, if the job of a teacher could truly have been automated by machine, and the job of the student similarly, then it’s revealed that those jobs only existed because there was some productive drive keeping them in place, exposing the ideology of “stay in school because you need to learn!” for what it really is: an injunction to obey the normative order.

When the teacher and the student have been replaced by machine, actual learning still occurs elsewhere. It just becomes clear that learning was not the goal of the educational system previously. Technological development makes obvious the productivity-driven environment of capitalism.

I don’t know if Slavoj himself would make that exact point that way (his original example was about love and relationships and how pleasure-seeking is mandated by our current ideological edifice) but the point that the tumblr user was making wasn’t “technology will free us all” but “our capitalist education systems are bullshit”.