Monero, like most cryptos, is very volatile[1]. If I owned a small business and was looking to accept crypto payments, this price uncertainty would mean I'd only use it if I could quickly cash it out to something stable, most likely using something like BitPay, which then negates the p2p aspect. The prices on the shelves wouldn't be denominated in units of XMR either - they'd be in the local fiat.

For crypto payments to be accepted in businesses in the above scenario (and therefore become as mainstream as Visa or Mastercard), a robust stablecoin would be required, like what MakerDAO[2] is trying to achieve. Even though I've invested in them, I'd ultimately give them perhaps 10-20% chance of succeeding. Their product is incredibly hard to wrap your head around.

However, if Sai or some other stablecoin can achieve quick, cheap transactions, then it's possible that consumers will use it for everyday spending. Big "if" though.

[1] https://coinmarketcap.com/currencies/monero/

[2] https://makerdao.com/

Cryptocurrencies are very volatile because they are very new not because anything fundamentally worse compared to fiat.

If they some day will be accepted as a regular currency and you can buy everything you need with them then there is no reason to go back to local fiat. Then the prices on the shelves would indeed be denominated in units of XMR for example.

That is indeed a big if though.

The future is being downvoted on HN of all places.