What I explained were the consequences of having an earlier lower fee tx be the one in the longest chain. This means RBF provides no guarantees, it means that in BTC you must wait for confirmation(s) - as you restated. So BTC cannot be used as P2P digital cash, as it was intended.
RBF is not supposed to provide a guarantee, it's quite the opposite - it's a warning that the TX can be replaced. Have fun arguing with your straw man.