That remains to be seen. Assuming they do opt to incorporate blockchain tech into their infrastructure, it's the way in which they implement it that will determine what level of security it offers. It's not a case of just saying "blockchain is more secure", throwing it into the mix and expecting it to work. Different blockchains have vastly differing standards of security. If they're not careful, the banks might even manage to build something less secure than what they currently have.
Totally agree. Otherwise blockchain tech is just a solution looking for a problem.