If many banks join that cryptocurrency, maybe they can get it. But the difficult thing when the banks try to gain ground in our subject, decentralization. This is in danger, I hope they do not achieve great control.
When many banks join to make cryptocurrency, they will definitely promote their creations with legal and safe labels. On the other hand, bitcoin will face many obstacles because the bank's cryptocurrency is more dominant in its area. Fortunately bitcoin doesn't depend on the bank, so it doesn't feel too much of an impact.