If Satoshi becomes so expensive that it cannot be exchanged for anything, it may create some problems for using bitcoin in everyday transactions. However, in this case, there are several possible solutions:
1. Dividing Bitcoin into smaller units: If Satoshi becomes too expensive, it is possible to divide bitcoin into smaller units to facilitate transactions with smaller amounts. For example, you can create a new unit equivalent to 1/100 Satoshi to be able to conduct transactions with smaller amounts.
My only confusion is as to how one could continue to subdivide bitcoin without effectively "creating" more bitcoins, thus bypassing the 21 million unit hardcap. Its not that I don't believe you, I suppose I have the wrong understanding of what it means to make a smaller and smaller unit. Would that not merely be increasing supply, which is not supposed to be allowed? Or is it something that merely exists on a spreadsheet and doesn't really impact the value or supply or bitcoin overall?
If there's a smaller units than satoshi then it wouldn't be a mere increasing supply as it is already exist and people haven't used it yet but if it's in lighting network then people may have used it already since there's already a unit smaller than satoshi which is called millisatoshi which is as you can see smaller amount than satoshi then it wouldn't be a problem if ever that will happen in the future. I am not sure if there's a unit that is smaller than satoshi in bitcoin main network. If it is possible to make changes in bitcoin where there will be a new smaller unit than satoshi then that won't be a problem when satoshi price is $10k. In my opinion, I don't think that will happen in the future because as far as I know satoshi is the smallest unit in bitcoin unless you use lightning network.