I'm just rephrasing the above. Don't join. If being a military officer isn't a primary motivation for you, you're very likely to be miserable. There's always a slim chance that you surprisingly love it, but that's a lottery ticket. Plus, this is a very uncertain time to join. In previous years, at least you generally knew what was in store if you did join (with a margin of error, of course). Now? who knows. Too much in flux to predict what might happen with GME and with your career in the service.
$400k with interest is a lot of money. Anyone who says otherwise has lost a little touch with what is reality for most people. That being said, the majority of people completing medical school do not take a military scholarship, and they get by. It's a big sacrifice, to be sure. But so is the military, and I would argue that the military is a bigger sacrifice. Paying for it yourself is going to involve a longer period living in the poor house. It's going to involve looking for jobs that offer repayment plans. Its going to involve possibly working in an area you don't necessarily love for a few years. But all with the guarantee that you're practicing medicine in your field without risk of deployment, skill rot, or operational billets. Plus, military bureaucracy is a whole thing unto itself that would make the Byzantines scratch their heads. Not saying there's a perfect work environment, but the military is pretty ridiculous.
Also, if you end up going in to a high paying field, $400k plus interest starts becoming much more edible.