The data is unambiguous in both directions and people usually only quote one half. Large fortunes are made through concentrated ownership of a productive asset the owner controls — and the owner-labour finding means that asset's value is partly a claim on continued personal effort, which is a risk most owners never price. Large fortunes are kept through diversification: the top 0.1% sit at 49% public equities. These are two different jobs done in sequence, not a debate to pick a side in.