Banks will traditionally be against anything that has the potential to affect their business. Traditional banks have been against even fintechs because they reduced their customer base, cryptocurrency has the ability to also affect the customer base of these banks that is why they are against it.
They hate it but in reality they also benefit from fintech. How?
They steal the ideas and concepts related to fintech. They have started adjusting their services to keep up with fintech and it has only made theirs and our lives better. Soon enough they might also start using blockchain mechanisms. They are definitely looking for ways to improve on their methods so as not to lose customers.
Who wouldn't want a decentralized system that gives you the opportunity to be your own bank? People are fast realising that they have been cheated by the banks for years, hence the rapid movement from the banks to a better alternative (crypto) that offers what the banks cannot give. Why wouldn't the banks hate this new invention that has exposed most of their secrets to the common man.
People are wiser now, it is better they adopt Bitcoin, a decentralized system with a currency that appreciates over time and with good security, than stick to the banks that steals from them with the disguise of helping them keep their valuables safe.
Banks will hate, but it will not stop the mass adoption of bitcoin.