>we could be doing so much better as a species
...relative to your expectations. If your model of the world (from which these expectations arise) was accurate, it would predict the world as it is, opposed to an ought. Things are not good or bad. They just are. And how we react to this status quo then can be evaluated as good or bad subjectively, and the closer you look at the metrics you use for the evaluation, the more of it will be culture, local, and meaningless in the greater scheme.
If you don't like how individuals allocate their resources, give them a reason to do it differently. Just being sad because in a theoretical instance of our world things could be better, won't close the delta between our is and your ought.
>We need to tax billionaires of everything above 10 billion dollars
this, for example, is based on the assumption that our core problems are derived from an unfair distribution of resources. While you can certainly make that argument, I would strongly recommend you to reconsider wether thats truly the root of our problems - it's not. Try to understand us as a collective organism of nodes that exchange information. Try to understand the underlying systems that drive our behavior. Go deeper. Understand for the sake of understanding. The more you judge with your heart, the more blind your brain becomes, and that won't get us anywhere. Cheers!