I don't have a dog in this fight, having no children and not being in "need" of an inheritance, but the ability to pass assets from generation to generation seems to be yet another way to constrain economic and social mobility.
It's by no means the biggest constraint, and inheriting wealth is by no means a guarantee to future prosperity but in the U.S. those born into the top quintile are most likely to remain in there, likewise for those born into the lowest quintile.
Given how badly the other key influencers seem to work against the poorest, education, healthcare, paucity of opportunity and that they seem to be getting worse in the US (and the UK) then it doesn't look good for future mobility.