Everything has a price. I wouldn't like it. And I'm not going to say it's impossible. But even in that hypothetical scenario, I imagine they would extract an extremely large pound of flesh in exchange for it. They haven't had enough time to extricate themselves from USD assets yet. Instead of providing excess liquidity, I am thinking only 50% of the shortfall, and in exchange for unlimited access to EUV, complete withdrawal of all sanctions on all Chinese companies and individuals, etc. the list should be endless.
If the US wants China to help them out this time, sure.
But the price that the US will have to pay would have to be MASSIVE in order to be effective.
1. Complete and permanent lifting of all sanctions and bans against China on every field involved (economic, trade, technology, society, military, etc).
2. Taiwan will submit to absolute, eternal authority of Beijing. The PLA will be stationed on the island on a permanent basis.
3. Complete and permanent withdrawal of US military forces from the First Island Chain, and the complete demilitarization of the Second Island Chain for a period of 50 years.
4. A new international system will be formulated, and a new international rule of order will be established. China will become one of the major decision makers, with equivalent status, authority and power as the US-led West.
Of course, we already know that unless ZTZ-99A tank columns are moving freely across the National Mall of Washington DC, the US would never agree to any of those above. But the fundemental laws of nature will remain the same -
Every debt incurred has to be repaid.
Whether the US will repay its debt through reconciliation with China, or be destroyed and fissile apart from within, or be flattened by nuclear hellfire - The choice is for Washington DC to make, not Beijing.