and talking about leaving the bank doesn't seem like it's going to happen,
there's no harm in adopting both and it's a good thing
Yes the trust level for crypto will increase if that adoption by bank will happen, knowing skeptical people want to have or see a solid foundation which they can rely on since we can't deny that there are people tagging bitcoin as scam and the presence of the bank will really help them determine that bitcoin is really a good crypto, and maybe this adoption made by legal institution can help bitcoin market itself from people who doesn't know about it yet.
Since the majority of what we need in this world can be bought by fiat only, there's no way bitcoin will take over and people will use bitcoin for everything. Bank will produce money and people will use bank even bitcoin will become more popular, so it's fiat (bank), then bitcoin as an alternative.