There are plenty of reasons why someone like Jamie Dimon shouldn't utter more than a few noncommittal syllables about a thing like bitcoin. For one, as soon as you come out calling it a fraud and saying you'd fire anyone who traded on it, everyone's going to freak out and you're going to have to keep on answering annoying questions on the topic, ad nauseum. Eventually the folks on the media relations team will also get tired of having to put out brush fires, and you'll be muzzled (even if that muzzle only kind of works).
But the worst part is when you have to eat crow and do the thing you just professed to opposing with every fiber of your being. Eventually, because fate can be fickle and fraud can be remunerative, you'll have to dabble in bitcoin:
J.P. Morgan is considering whether to provide its clients access to CME’s new bitcoin product through its futures-brokerage unit, a person familiar with the situation said. That means the bank’s customers could use it to place bets on whether the digital currency will rise or fall, while J.P. Morgan collects fees for such services. The process has involved assessing whether there is demand among J.P. Morgan’s customers for the proposed CME bitcoin contract, according to this person.
This was the inevitable consequence of CME launching into the crypto space with a futures product pegged to the value of bitcoin. Now that traders can buy bitcoin exposure with a simple mass-market derivative, they can avoid the sketchy and bewildering process of actually purchasing the tokens themselves. That means no worrying about trusting some janky third-party exchange of indeterminate origin and probity, no squirreling away physical private keys to protect your lucre, no bonkers transaction costs. I.e., none of what makes bitcoin fun.
So why wouldn't JPMorgan offer bitcoin futures execution services to its more risk-on clients? The only loss here is reputational, specifically Jamie's reputation for despising bitcoin. Which is a dumb reason not to make your clients happy and earn a few bucks by doing something you basically already do. And if you need any other reason, just do it so you can beat Goldman to the punch.