[nhinck]

The claim was: "Each round, the collective wealth goes up 5%, no matter how many rounds you run. "

And this isn't true.

[kgwgk]

Do you mean that it's not true that "in one round, the collective wealth goes up 5%"?

I could agree with that.

(However, if you add "in expectation" it will be true for one round and for each round no matter how many rounds you run.)

[nhinck]

For a finite population and starting wealth, the collective wealth will tend to 0 given enough rounds.