I don't think it's right to say "privacy/sovereignty". As gestured towards in the source article, Japan and Korea have joined the US's preferred data privacy forum https://www.globalcbpr.org/. Data sovereignty is not a common idea outside the EU, and AFAIK even the current American government doesn't object to US citizens' data being stored in foreign servers under foreign jurisdiction.
Data sovereignty is almost the default in Korea and common in Japan. It has been a common idea there for decades, in fact there are laws about it. The big corps there were plenty familiar with the CLOUD Act and such many years ago when 99.9% of EU corps couldn't give less of a shit. Percentages are completely different.
Joining of a forum is meaningless in itself, the actual actions of the governments and businesses in their usage vs abstinence of US clouds is ehat matters.
Joining a forum is meaningless in itself, but it's a pointer towards broader differences in attitudes towards enforcement. Japan is a big country which multiple companies I've worked for do business with, yet I've never had to take a training course about what I, not living or working in Japan, must do to comply with Japanese data protection law.
(Should I have had to, and companies just don't bother because Japan is smaller? I guess I'd believe that, although I'd still be surprised that I've never heard about a Japanese data enforcement action against a foreign company.)