There are many things that are scarce that don't have a hard cap on supply. Gold for example.

Bitcoin is also not a unit of account or the most saleable good (neither is Monero or any other crypto)

A requirement of money that Bitcoin doesn't have (or weakly has) is fungibility (uniformity, indistinguishable), but doubt we are ever going to see eye to eye on that. Yes, I know lightning in isolation is fungible, or can be, but Bitcoin as a whole is not.

"You don't ask nicely that everyone else not spend your coins; You just protect them using a cryptographic key.

Similarly, you don't ask nicely everyone else not distinguish your monetary units; You just make them *technically* indistinguishable AKA fungible." -binaryFate