Can this be what would later happen?
Yes, the CBDCs will surely be a little bit harmful for traditional banking systems and also for fiat currencies. The new generation wants currencies that should be digital in nature and CBDCs were introduced by keeping those demands in view. The traditional fiat and banking system will also be working for many upcoming years, but surely they will end one day because each new system ends the traditional ones.
I don't think that the CBDCs will have any impact on the number of jobs and I'm quite sure that CBDCs will also be handled by banks in most countries if not all. I believe that CBDCs may be helpful to create more opportunities of employment in banks if they are integrated with the current banking system. Other than that I don't think that they will harm banks or traditional fiat in any worse way.