ZickZack

No, it’s built into the protocol: think of it like as if every http request forces you to attach some tiny additional box containing the solution to a math puzzle.

The twist is that you want the math puzzle to be easy to create and verify, but hard to compute. The harder the puzzle you solve, the more you get prioritized by the service that sent you the puzzle.

If your puzzle is cheaper to create than hosting your service is, then it’s much harder to ddos you since attackers get stuck at the puzzle, rather than getting to your expensive service

It’s $\mathbb{X}$ or unicode 𝕏 (U+1D54F)
Maybe he really likes metric spaces??

They will make it open source, just tremendously complicated and expensive to comply with.
In general, if you see a group proposing regulations, it’s usually to cement their own positions: e.g. openai is a frontrunner in ML for the masses, but doesn’t really have a technical edge against anyone else, therefore they run to congress to “please regulate us”.
Regulatory compliance is always expensive and difficult, which means it favors people that already have money and systems running right now.

There are so many ways this can be broken in intentional or unintentional ways. It’s also a great way to detect possible e.g. government critics to shut them down (e.g. if you are Chinese and everything is uniquely tagged to you: would you write about Tiananmen square?), or to get monopolies on (dis)information.
This is not literally trying to force everyone to get a license for producing creative or factual work but it’s very close since you can easily discriminate against any creative or factual sources you find unwanted.

In short, even if this is an absolutely flawless, perfect implementation of what they want to do, it will have catastrophic consequences.