I'm not sure who made the argument that inequality is unavoidable. The argument is that it's a strong tendency and a common scenrio without structural provisions.
Rich people who benefit from everyone else thinking this is the natural way of things and thus they are not to blame. The same kind of people who call workers arrogant and say they should be thankful to employers and be put in their place through unemployment.
https://tribunemag.co.uk/2023/09/the-viral-ceo-shows-the-tru...