The argument still holds. As long as there is a tiny probability for you or someone else to lose their private keys, and I don't see how that probability can be

The argument still holds. As long as there is a tiny probability for you or someone else to lose their private keys, and I don't see how that probability can be reduced to zero, bitcoin supply will approach zero over time. And I don't think we are talking about some theoretical astronomical time span here - after a few hundred years (assuming in a few hundred years someone still cares about the bitcoin ledger), the proportion of lost coins must be huge - just think about people passing away without providing a way for their heirs to find the keys, maybe because they die young or because they have no heirs etc.