The message means to acknowledge the value and legal tender status of cryptocurrency!
You can understand it this way: holding Bitcoin and buying gold are similar asset attributes; you can put gold in a bank for custody, and you can also put Bitcoin in a bank for custody.
Of course, this refers to cryptocurrencies, not all cryptocurrencies qualify. Those on-chain shitcoins and meme coins have no value and are just coins for scamming; I believe banks will not provide custody for them.
Banks will also conduct risk control; Bitcoin can definitely be held in custody, and Ethereum should also be possible. Other tokens depend on the individual banks' own recognition rules.
I think there is no need to gamble on uncertain tokens; just hold onto certain tokens, like Bitcoin!
New message: The Office of the Comptroller of the Currency (OCC), the Federal Reserve, and the Federal Deposit Insurance Corporation (FDIC) have released joint guidelines for cryptocurrency custody. Banks can hold cryptocurrencies for customers, but they must comply with strict existing laws. Banks (not customers) must have complete control of the keys to gain full control = full responsibility.