One of the big problems with using bitcoin for something like this is you're not just sending money. Your converting to a different currency, sending money, and converting it back. It would be akin to me wanting to send money to my Dad by converting it to Euro first, sending it, and him converting it back to USD. Neither of us have any interest or use for money in Euro or bitcoin. We both have/need USD.
You also get the volatility of bitcoin. If I send $10 to my Dad in bitcoin, it might be $9 by the time he gets around to converting it to USD. Or $11. Bitcoin could plunge in value (for seemingly no reason that I can tell) and be worth $5. I have no way of knowing what the value of that will be for him when he gets it.
If I want to send my Dad $10 on PayPal, he gets $10. He gets it instantly in his PayPal account as $10. If he transfers it immediately to his bank, it'll be $10. If he transfers it next week, it'll still be $10. It's guaranteed in value.
Also, I don't know if this is still the case but dealing with bitcoin is a pain. If I want to buy bitcoin at Coinbase and I don't have a credit card linked to my account (until recently, you couldn't even use Mastercard), I have to wait a few days for my BTC to arrive, even though they are directly linked to my checking account. I have no idea what the value of my BTC will be when it finally arrives a few days later. I have to send it to my Dad, he has to sell it back to USD (at least at Coinbase, at a lesser rate than buying it). The value could change dramatically at any of those steps.
And if you want to add a card at Coinbase, yeah, that's fun. When I added my card, my bank immediately kicked the attempted authorization out for fraud reasons. 10 minutes later my bank called me about it and I approved it, but the Coinbase told me I couldn't try again for a week. So I had to wait another week before trying to add my Mastercard again.
Bitcoin has a lot of usability issues for non-tech people. And using it for a simple USD->USD money transfer is like using a jackhammer when you need a scalpel.