If we speaking kinda teoritally.. well, I guess it is possible sometimes.. maybe after all bitcoins would be mined.. and price could be more predictable.. but I'm sure banks will not offer for you very good conditions...
They will earn money for themselves first of all..
when it happens is already in the sure. big profits will belong to the bank. and we will only get a minimal profit. because nagara also will control for state income. which means it may be able to boost the price of crypto or vice versa.