It's not just some gold coins, it's also the matter of $12.7 million invested in his research endeavor. If you raised $12.7 million to start a company like Theranos you'd also be looking at a steep prison sentence for securities fraud.
He would be free if he provided the power of attorney.
If you believe his punishment is just you should believe in debtors' prisons.
If you don't believe in debtors' prisons, you should object to this.