That's the thing, a lot of very selfish people like to pay lip-service to communist ideals but the minute these people are put into positions of power they immediately start showing their true colours. Humans can be very selfish but we can also be very caring and selfless too. The thing is, the ones who do care aren't usually the ones looking to be in power.
I think that's a huge insight, and you can use questions like that, "What is the *actual* motivation?" to any philosophical idea like nihilism, or like free will, or anything. People try too hard to deal with the facts being presented, the ideas, the reasoning. Just throw all that out and look at the person. Why are they saying what they're saying, given what we understand about humans? Asking that more fundamental question, is a much more reliable path to truth than playing the former language game of ideas, narrow facts presented, and so on.
For nihilism specificially it's just self-defeating, it makes no fucking sense at all. There's no meaning, huh? What? Then... what the fuck does that even mean? That thing you just said? Gleerpordfk gkj ajksd gl? What are you even doing? Oh... you mean *moral* nihilism. My bad. *People* don't actually matter. Okay. Put your face into the hot stove now then. Oh... what's that? You won't? Well... why not? What better way to show it's all irrelevant? It would really strongly signal a commitment to what you claim to believe. Hmm... I still don't smell burnt human flesh. Strange.
Anyway, the more you deal with the actual narrow reasonings back and forth, when they're full of shit, the crazier you eventually become. Because that game never ends. It is like a game children with infinite energy play, where it won't actually end until force intervenes to stop it. Someone can infinitely justify and counterargue and do all kinds of tricks and games with words that go nowhere, even if they look like they're going somewhere, or even if lots of important people take it very seriously. The technical term for this mentally ill circus is "academic philosophy"
So just ignore the presentation, it's superficial. Look deeply (either in yourself, or in others), and ask, "What's the motivation? What's the benefit from this?"