Please read the link again, and/or work on your reading comprehension skills. The part you talk about is referring to not showing up to court when summoned, not failing to pay a monetary judgment.
Generally, once you have a judgment, it's up to you as a creditor to enforce it. You can do this in a number of ways, including enlisting a sheriff to help you (for a fee). But the debtor doesn't end up in prison for not paying a judgment.
Do you see how "not showing up to court" != "not paying a judgment"? Like I said earlier, the only way you can end up in jail for not paying a debt is if it's child support or a fine. These exceptions are perpetually controversial because they're basically debtors' prison, although supposedly inability to pay is a defense to the contempt charge.
In any case, I've thoroughly skewered your stupid "send me an email saying you'll pay me $10000" or whatever hypothetical. Unsecured creditors have no ability to force you into jail. Just make your court appearances, stupid.