This is already how astronomy, and specifically cosmology, research works in the US (and most other places). Data is made public within a short period of obtain

This is already how astronomy, and specifically cosmology, research works in the US (and most other places). Data is made public within a short period of obtaining it on a schedule (usually less than a couple years) that is set before data is taken. It is far from clear that the Chinese government supports this type of open data sharing.