This is somewhat ironic given that all five of the paper’s authors are East Asian.
So it may be that the data sources the authors had are biased too. In any case this is an issue that should be addressed.
Why is that? This is just a demonstration of a new idea with existing technology, not some ready to deploy app for 2 billion people.
Possibly (probably) the cognitive load on people might lead to bad A/B test results, but it would be a curious thing to explore - cultural bias would get a bit of a beating I'd imagine.