Looks like he's starting a the end of a bachelor's degree. It's a sane simplification since it should be the same for both fields.

For medicine, undergrad debt is pretty tough since you really have no way to pay it off. It just accrues.

Yeah, exactly right. Whether you do pre-med or an engineering undergrad, you should have the same amount of debt/time. Though of course I simplified everything to not really account for interest.

Assumedly, an engineer would be able to pay off their undergrad debt much quicker than an MD.