It seems pretty clear to me where I got it from. You are definitely fine with letting people live in misery at the best. It's pretty simple, there is no "actual what the fuck" about it.
Funny that you comment on nature, when civilization has made a lot of the horrible things that have to be dealt with in nature a lot less relevant. In nature animals are violent to each other, and will kill each other even of their own species. By your logic you must support killing each other, otherwise your argument about nature would be totally hypocritical.
The more civilized a place the more people can do their own thing without worry of harm or their needs being met. What you wrote below has nothing to do with a basic income. A basic income will make people less afraid of moving employers for example, making parasites that employ people in hideous conditions lose power. Threats from those psychopaths will have a lot less punch. That is a massive gain.
A basic income does not look like it will not alter how much people work. As an example, the MINCOME project showed that the only new mothers and teenagers worked substantially less in an actual experiment with a form of basic income, the people who work will still work. I will not repeat other sources here, any reader can look it up if they want.