"In the draft, manufacturing technologies for high-performance magnets using such rare earth elements as neodymium and samarium cobalt were added to the export ban."

It didn't mention restriction on export of mineral or magnets themselves. Pretty sure US would restrict similar technology export to China.

BTW I don't think China ever exported such manufacturing technology. Formalization is likely due to the desire to show some ability to retaliate against western SME export ban.