If the world actually equitably shared wealth, the western would have an absolutely astounding drop in our incomes and quality of life. Few would accept this. The average person in the first world has a massively higher quality of life than developing countries.

This is why the only long term answer is technological development, without which we would all still be subsistence farming (and all poor). It would be nice if we had more social advances coupled with this, but that is predicated on human nature taking a different turn than it has historically acted.