When the banks start to advertise bitcoin as a good investment, hence we should be suspicious then because its never the nature of a centralized institution to praise a decentralized asset or investment. It could be the result will leave them a highly favored outcome, or eventually they will blackmail bitcoin in the end, so we should be careful trusting banks for bitcoin. It's more safe to trust your own instinct, than to trust the known enemy of bitcoin.
I remember years ago when banks were speaking out against and warning about bitcoin, we said they were anti bitcoin. But now they are promoting bitcoin very well and there is no more hostility, we say they have a bigger conspiracy and need to be more careful. So, in the end, what exactly do banks need to do to make you happy? LOL.
Bitcoin ETFs are also centralized entities and they are attracting customers to invest in bitcoin through their centralized services. Why do none of us complain, doubt or protest about it? On the contrary, many of us are excited and supportive because they are making the supply of bitcoin more scarce. Why are we angry with banks when they do the same thing?