Remember that one person can have multiple pseudonyms and that a lot of real life proof of existence or work cab be crafted to fool a typical person with a lot of money.
People have ran cons in real name, and succeeded. Given pseudonymity not linked to any real assets (unlike a company), it's even easier.
Heck, someone can claim to be a given Nym while not actually being that person, blockchain does not link Nyms to a legal person, and neither does any DAO known to me. The only proof would be paying gas to whoever tries to strike a real life contract off a big account with visible history. And even that can be faked if you're diligent enough and hunting for whales. Good luck fixing it.
If a government backed a DAO and had some link, there goes pseudonymity but you also have some legal recourse.