I disagree with this view. I think the metaphor captures some elements of the experience, but it doesn't capture enough.
A craving feeling arises to have fun. The craving exists there because it feels nice. This also implies that you feel less nice than you'd like to feel. This craving doesn't happen that often, but often enough that you're curious about taking drugs.
You try cocaine. Suddenly you feel energized and amazing, this is how you always want to feel! The effect wanes after 20 minutes, you take it again and you feel amazing. You're starting to do this every weekend. Cocaine gets associated with the craving feeling for fun.
After a few months, whenever you feel like your normal self, a craving feeling arises. This feeling is now a mix of wanting to have fun and wanting cocaine.
The thing is, where I think the debt metaphor breaks down is that this increase in craving acts a bit different than actual debt.
Many addicts feel strong cravings for years afterwards, and it only very slowly decreases. Once hooked again to the substance, it's easily back to previous all-time high levels. Psychologists claim that in conditioning processes, it's impossible to delete conditioning (called extinction). So you can never truly repay our debt.
Moreover, once your craving is extinct (for as much as possible) it's really only dormant in reality. Make one wrong move and you're quickly back to rock bottom. With debt, if I pay back my debt of $50K, then splurge for another $1K, I am not back in debt with $50K. This is however how addiction works.
Finally, the debt metaphor doesn't capture the uncontrollableness of cravings that are arising. You have no free will in what spontaneous thought or feeling arises. This is quite easily seen when you're sitting still and try to do nothing: your mind will still chatter away, you'll still feel things based on that chatter. In quite a few cases it's impossible what your mind will show you next. The same is true for the cravings that an addict gets with a drug. Sure, the craving will arise when one starts to talk about it, but it may also arise when somebody twitches their leg, because the muscle tension is super vaguely associated to a memory when one was partying with the drug, but the person is not even aware of that association or that it's part of a memory.
Disclaimer: I'm not a drug addict, but based on my personal life experiences, I think it's fair to say that I have enough experience how it must feel like (I experience a mild pull to alcohol, a strong pull to caffeine and an overwhelming pull to videos and video games).