I acknowledge and sympathize with the pain this will cause, but in regards to Japan itself: Good for them. Not because it is a rightward shift, but because it is a shift toward pragmatism in the face of the inherent tension between respect for all people and respect for one's own people and culture.
In my humble opinion, an ideal world is a liberal one with cherry-picked, tightly controlled, practical conservative elements that boldly take on the intimidating job of maintaining the balance between love and reason.
This is going to cause more pain to the Japanese people.
There is nothing pragmatic about kicking out the workforce you imported because of a shortage of native labour. The pragmatist stance would be to accept those differences, and focus on addressing/alleviating them. Cutting your nose to spite your face is more idealism than pragmatism.
I mean, sure, so long as they're willing to deal with the consequences of an aging population and a shrinking workforce.
This is a shift away from pragmatism; pragmatism would be acknowledging Japan's economic need for immigration.
Whether Europe or North America have a problem with too much immigration and not enough integration is debatable, maybe - and I suspect that's where your perspective comes from - but Japan decidedly does not (maybe too much tourism, and I feel at least some of the antagonism towards foreigners comes from that, but no matter). Immigrants still make up a very small percentage of the population, mostly in Tokyo; given the existing challenges with immigration, they tend to be extremely diligent, respectful, appreciative of Japanese culture, and hard-working.
This is just a populist conservative government pandering to the some of the worst aspects in society to distract from their failures.