OK, interesting boundary condition thought experiment, but the stated cause seems janked. Isn't Dimon just shifting blame here for a job he's supposed to do but is shirking? His job, as a bank, is to broker loans for a certain deposit ratio to create money and keep the economy going forward. He doesn't want to assume the risk of those loans, but his bank gets penalized for not keeping a proper deposit ratio (and not giving loans to spur investment), so to avoid penalties for that, he just taxes depositors so that he doesn't have to mess with the job of actually banking, despite being granted various affordances to do so. Instead, he can suck off the usual surcharge over the Fed interest rates on hundreds of billions, no-brainer profit, and deposits a performance bonus without having to bother with the actual business of making loans. Yes, over-saving locks up capital, Japan has this problem, but banks shirking their duty of making loans similarly hinders GDP growth and is really bad for small businesses and people building really cool shit in their garage in Palo Alto that later grows into, I dunno, HP or that weird little company with the fruit logo.