Majority of people still think traditionally and would choose bank deposits over crypto. Banks are not going anywhere.
What the majority is thinking now doesn't really matter in the big picture. It did not matter that the majority of people in the 80s preferred to send a letter than use their modem to send an email, or even buy a fax machine. Sure, the majority would still choose a bank, but BTC is where personal computers and the Internet were in the 70s and 80s. 30 years from now it may be a completely different world. If you don't believe me check out how much the world has changed between 1980 and 2010.
I only disagree when you say "30 years from now": when I look at the recent past, I'm pretty sure that in just ten years - or less - we'll have a complete revolution in the economic system, due to bitcoin and - muchmore - to the blockchain technology.