Well, not exactly. The debt is still there, they just can't force you to pay it. Exceptions apply, like student loans, and they can probably still claim property in the case of bankruptcy or inheritance.
Not empty just extremely low. Low is worse then nothing. Good luck getting any credit after this. Then again, if the crypto actually grew, it may not matter. You would need at least half a million in profit to be worth all the effort of this scheme. Still only making about 70k a year at that level. Assuming you did 7 years and didn't have to pay anything like prison rent. Seems like a bad investment.
Low is not worse than nothing with credit. Low credit means you exist. When you have no credit score everyone starts to question if you even exist. I may have personal experience with that.
Well it works where if it's non government debt and you don't pay for 7 years, it falls off your credit report. Of course if you had a car/home tied to it they would have taken it at that point.
But honestly at 5 years the collector will have mostly given it up and sold it to a debt collector for pennies on the dollar who call from time to time when they have nothing else to do.