I've probably told this story before, but a project I was working for about 12 years ago was slotted in under the remit of the city centre manager and he told us about the lengths they were going to in an attempt to attract Waitrose to open in Parc Tawe 2. They put together an incredible package for Waitrose that included nominal rent and other financial incentives to open in Swansea. Waitrose did a feasibility study and concluded that it still wasn't worth it to them, that there simply wasn't enough money being spent/shoppers visiting Swansea to make it worthwhile to them.
The only way the council could have bent over backwards more would be to pay retailers to open here and I doubt many residents would think that a good use of council funds.
As ECB and others have said, the majority have chosen the convenience of out-of-town shopping or the convenience and cheaper prices of online shopping to visiting our city centre. If everyone who complained about the state of retail in the city centre actually spent money there, it would probably be thriving.
I'm not here saying the council are great, many poor decisions have been made by successive councils. Bendy buses, the endless tinkering with traffic on the Kingsway and likely many more that aren't coming to mind right now. The pivot towards living accommodation, leisure, dining, etc may not work in the long run, but as I've said, I haven't seen a better suggestion made. What they do with the Civic Centre will be interesting, as that will be an attempt to connect the beachfront with the city centre.