No one ever says this about m/billionaires or their children. There are always going to be a few people taking advantage of a system, that shouldn’t be a reason to punish everyone else.
Yes, they do say that about the children of wealthy people. The conventional wisdom is the first generation earns it, the second spends it, the third is back where the first started.
Wealthy people are well aware of this, and will often try to make their kids earn their things, send them to a military school, etc.