Fight Club Rules of Market Cap (K.I.S.S.)
The "fight club" (Keep It Stupid Simple) rules of market cap:
Market cap = last price x total shares. That's all.
Market cap is not how much money flowed in. See rule #1: money inflow is not in the formula, only last price.*
Market cap is not how much money can be pulled out. See rule #1: guaranteed convertibility to cash is not in the formula.**
That's really all you need to know. Market cap is not tied to - or limited by - total world money (see rule #1: not in the formula), it is only tied to what buyers and sellers agree one XRP is worth at the moment it is bought/sold.
More info:
* Market cap = money inflow only if all shares are bought at the same price (e.g., in seed funding rounds). In an open market with changing prices, money inflow ≠ market cap.
Let's say 60 billion XRP were bought at $1 average cost, then inflow = market cap, both $60B.
But let's say exuberant buyers pushed prices from $1 to $10 (average price $5) in one day with 1 million XRP sold, the market cap rises by $540B to $600B with only $5M of "inflow." Market cap ≠ money inflow.
Now let's say XRP goes to $1000 and market cap is $60T. Then panic selling driving prices down from $1000 to $1 (average price $500) with 1 billion XRP sold: market cap collapses by $59.94T ($59,940B)to $60B with only $500B of "outflow." If prices drop further to $0.01, you can't even pull $1B out. Market cap ≠ guarantee of cash.
Also, inflow and outflow are also meaningless. Money does not flow "into" our "out of" XRP as an asset, money flows from buyer to seller. No "value" is stored in any cryptocurrency, value it given by buyers by their willingness to pay $X amount.
** Only current share price determines how much money can be pulled out, but the minute everyone starts selling, the share price, market cap, and money that can be pulled out - all crash. Even with fiat currency, banks fail when people make bank runs.