I think its a silly response to the problem, yes if you were near the lever and you so happened to know one of the groups then you might argue pulling the lever one way or the other.

But is that simply you justifying your actions?

The problem isn't absurd when posed to humans because, how about the scenario where you don't know either person and you need to make a decision in a matter of seconds. That's the point.

If my mother was on one of the tracks, I might justify my actions to pull the lever and have it veer into the other group, but that isn't necessarily a morally correct decision.

The author in the article says that the problem is absurd when posed to humans, then goes onto applying the same principles of the problem to AI and cars but does not say that the problem is also absurd with regards to AI, despite coming to the same conclusion.

The trolley problem came up a lot in The Good Place, which may be why discussions around it have suddenly become a bit more mainstream.