I believe what he means by this is the difference in the two protocols. Ethereum being proof of stake and Bitcoin being proof of work. Proof of stakes core principles (infinite supply, no halvings) will enable whoever is mining the most Ethereum to have majority control over it's network, in due time, that is. That and coupled with the depreciation in value of the fiat currencies that are used to buy ETF shares. That will lead to a massive increase in the current supply. It seems like a lose-lose scenario, imo. 

 That's my guess, anyway.