But you're partly right. Simulate random exchanges at random prices and the wealth distribution will come out Pareto.
However, we cannot conclude that because [a] random exchanges lead to a power-law dist and [b] we observe a power-law in reality, that [c] the real wealth distribution is tantamount to random.
For what it's worth my initial statement was meant to hold beyond income and wealth and generalize to say achievement and productivity and so a lognormal assumption was fitting as the distribution to pick. It also chimed well with grandalf's statement on how advantages multiply.
But you're partly right. Simulate random exchanges at random prices and the wealth distribution will come out Pareto.
However, we cannot conclude that because [a] random exchanges lead to a power-law dist and [b] we observe a power-law in reality, that [c] the real wealth distribution is tantamount to random.