In my opinion, there are two main reasons why the average owner of Bitcoin does not decide to use it as a currency. The first is that most Bitcoin investors are only interested in profit, for them Bitcoin is the same as investing in gold or stocks. Another reason is that most people think that the fees for sending BTC are too expensive since crypto exchanges charge them very expensive fees, which they think are blockchain fees.
My perspective is a lot of us using fiat will forever be chasing the better life, due to rising costs, and inflation. Basically, by using fiat you're accepting you'll forever be in the rat race, up until you retire, and what you've worked your entire life for, is worth jack all in retirement due to the inflation.
Bitcoin, gives you the opportunity that I believe other investments don't, mainly because I actually believe in the fundamentals. For example, the freedom, not relying on a third party, and the fact that you can't just keep pumping Bitcoin into circulation, means it should actually counter inflation. So, obviously we're all in it for profit, but it doesn't mean when it comes to using it, I'll be converting to fiat, I'll be using it to better my life.