Banks can’t legally just take your money and lock you out permanently. There are some actual regulations. Plus they have a proper handle on your actual human identity, which means you ought to always have a route to going somewhere in person and proving you’re the rightful owner of your money.

“Online” accounts have zero regulatory requirements, plus many of them aren’t necessarily directly paid-for, so they frame themselves as doing you a favor by letting you have it in the first place. And they usually don’t have a route to prove identity because they don’t record a legal identity (passport/SSN/etc) to begin with (not that that was an issue here, of course - in this case Apple didn’t dispute that they were the owner, just asserted that they were some kind of criminal.)