Yes, but which of these currencies are not operated by a registered or regulated entity?

Trick question: all of them are regulated, because they're operating within the legal environment of some country, plus the US tends to claim global jurisdiction on anyone selling things to Americans.

Technically everyone running a bitcoin miner is violating securities law. It's just that SEC enforcement of this is going after the most fraudulent crypto enterprises first.

That's a stretch. Bitcoin hasn't been defined (and probably won't be for a variety of reasons) as a security.

..and its always been ok to make coins. Its only printed money that was protected?

Nope, printed money is fine too. I used to live in Ithaca, NY, which had a fairly successful printed currency called the "Ithaca Hour": https://en.wikipedia.org/wiki/Ithaca_Hours

The only possibly illegal thing is you must settle your debts for state currency if your debtors request it.

It's to ensure company scrip remains suitably illegal.

It's legal in the UK: https://bristolpound.org/

Plenty of places take this money. I have never seen one in the flesh.