Unfortunately yes, the wealth we humans amassed over the years is distributed very unequal across countries, and even more unequal within all the countries. To be honest I find it the number of 20% owning 80% of the wealth quite high, I expected it to much lower. Just look at the super rich for example - worldwide the 26 richest people held as much wealth as half of the global population (3.8 bn people). It's kind of insane that there are not more civil wars around the world and people are demanding change. The wealth of the 1%ers keeps increasing even during crisis times, whereas the wealth of the largest part of the population remains constant. I don't think that the government is going to change anything, because they are being funded by the rich families. There is a huge lobby industry behind the politicians that finance all their campaigns. Without the money of the rich, the politicians would never get into power.
Laws are written rich for the rich, so it is clear that their wealth will constantly grow. Big money creates even greater capital with proper management, and rich people have enough funds to create financial institutions, where for their capiels they find the best options for investment.
Rich families are worried that their wealth passes from generation to generation, so their wealth are growing over many generations.
To some extent, it is difficult to understand why they need so much money, they will not spend it for several lives. Probably all this for the sake of power, because much money can be able to give great influence.