> Why should US or China matter if its open weights?

Weights aren’t source that can be inspected for nefarious tricks that would impact use, so, to the extent that there is a dinension of trust associated with nation of origin, being open weights doesn’t obviate the concern (I would argue, though, that there is very little reason to for nation of origin to be a significant factor in trust alone, though a finer grained consideration of origin might be sensible.)