They've proven themselves largely incapable of responsibly engaging with the market economy. Citizen earnings consist of a commons that need to be enclosed. I was skeptical of the 'owned markets' idea, though I've largely argued myself into it; the caveat being that the units should be owned, not a market as a whole.
Unsophisticated individuals can take on debt. The result is a mad rush to seize all their future earnings by selling them whatever useless crap can be frantically pushed onto them. Hence present household debt numbers.
You can't ban debt entirely. Sophisticated individuals will always flout those rules. Such a ban makes it harder for your jurisdiction to be rich, and it will either collapse into legalized debt or simply collapse.
Most states can't partially ban debt either. A debt license scheme will end up like the driver's license scheme: everyone gets one. Corporations will lobby until they can exploit consumers again, because present earnings are more valuable than future earnings. Second, having a debt license scheme is to acknowledge that some people are better than others.
Only feudalism and ancap can handle individual debt properly. A local lord can give a serf some minimal debt allowance. If they spend it on kitsch and nondurable goods, then it's revoked. Ancap can do it because the debt licensing scheme would have to be self-funded, and thus would be responsible. Equivalently: without FDIC loan suppliers, facing the actual default risk, will refuse to lend.
Wage slavery really is slavery. The average citizen cannot be free. At best they can be upgraded from slave to serf.