Two years ago, I got sick of banks whose services I found of lesser and lesser quality, and tried a bitcoin/VISA debit card, just to see if it was working. The idea was this: I make a bitcoin transaction to add bitcoins in card provider wallet, and when transaction is complete, I could exchange it for fiat that I could use with my card.
"when transaction is complete" is the culprint :) I needed to have fiat in the card so that payments to a cashier was instant. If you remove that step, transaction delays make it not realistic for buying stuff while outdoor, especially given current delays (but even two years ago, it wouldn't do).
So, for bitcoin to work without VISA (or alike) as third party, bitcoin will first need to find a way to make transactions instant.
The alternative, obviously, being to use it for purchases where transaction delay doesn't matter (like online purchases), or to use an other cryptocurrency for that.