Well, I mean, the alternative is for a US-based process to be put into place, followed (or led) by an EU process. The premise of my comment is that no matter who hosts the process, China isn't going to comply, so it really just comes down to the US and Europe.
And the US isn't going to comply either. Just like it never recognized the International Criminal Court in The Hague. In that respect it's at least as bad as China.
The only jurisdictions where training data is going to matter are in the US, Europe, and China. I think we're just talking past each other. My subtextual point is that none of this is ever going to happen.
Even if the UN only has a very small amount of legitimacy and credibility… that’s still far far better than literally zero.