I guess that's sarcasm but I don't really get it.
Just in case you mean it, that doesn't seem even remotely technically doable to me. And even if you managed to make people generate all randomness from a fixed PRNG with key escrow, you would have to check what they did with that randomness. If you're willing to go that far, the obvious way to go is to just ban the internet completely (and perhaps also people talking to each other).
But I was being a bit facetious. Most likely they would just to punish people who are caught using steganography.
Technically it's in reverse: the seed is random and then serialized into a human readable seed phrase but the deterministic key generation is already widely deployed.
But it only works on specially constructed grammars and not LLMs. :)
Now AI has done this for us. I suppose that under authoritarian regimes you will soon have to cryptographically prove that you generated your random bits deterministically from specific keys.