I don't see any difficulty in bringing bitcoin to daily use, it's just that people don't want to waste their bitcoins on day-to-day expenses while fiat has taken on that role very well.
But would you admit to me that bitcoin is more suitable for investment than a currency because of its finite supply? Moreover, if it was used as a currency, would people still care about it as it is now?
Indeed, people are not using bitcoin as a currency because they see it as an asset, you not gonna sell your Apple shares to buy a beer, but it's NOT the only reason. You can't deny that fiat does this role better, because it, again, stable enought to use.
Just take a look at the currencies people use, If you will pay attention to the Turkish lira, you will see that people don't want to use it because of its volatility. Yes, it's going only down while bitcoin can go up, but the point stays, people preffer to use rather stable currency in everyday life.
Of course, bitcoin is more suitable for investments than currency. Who the hell even invests in currency? You should compare bitcoin to S&P 500 instead. And yes, for me, bitcoin is the better investment. But it's not making a good currency out of it.