There weren't any laws passed banning Soviet associated agencies from publishing based on chain of ownership. Nothing to do with SCOTUS.

Read the opinion, the law was upheld on intermediate scrutiny. It doesn't ban based on content, it bans based on the designation of the foreign parent as an adversary. Since it's not a content ban, or rather because it's a content-neutral ban, strict scrutiny does not apply.

Without strict scrutiny, the law merely needs to fulfill a compelling government interest.