I know that increased productivity should in theory make life better for everybody, in practice wealth has been increasingly concentrated over the last few decades.
Having been to Africa and other really poor parts of the world, what you think of as "concentrated" looks like quality of living spread remarkably well over first world countries. So what if some people have an absurd amount of money?
In fact if you think about it, the stuff most people enjoy day to day, you aren't going to have a much better experience if you are rich. If you want an awesome laptop you can easily afford the same laptop a billionaire would use. If you want an iPhone you can max it out on a minimal salary.
You can have decent shelter, good food and a good life without a ton of money in most first world countries, in large part thanks to extensive infrastructure and rule of law. That looks pretty far from a model where all death is truly isolated and the well off are living in castles while you shovel pig shit and die of plague.