Doesn't it mostly stem from demographics? Developed countries are experiencing lower natural population growth so some have tried to make that up with immigration. Our economy and centralized fiscal policies generally assume a growing population. Without that, there's little that can be done. Automation can be used to increase productivity but that also faces a backlash from people worried about their jobs. People will blame the problems on politicians but the problem is beyond them.
I agree with you but we've seen that many people will just blame the immigrants. It's easier to blame change that you can visibly see rather than change that is forced to happen due to abstract demographic trends. No one has a good solution for this. If immigration gets too high, citizens will vote for parties that support anti-immigrant policies to bring it back in line.
Let's see, throughout US history at times it's been: British, Irish, Italians, Mexicans, Hispanics, Blacks, Japanese, Chinese, Vietnamese, Jews, Muslims, Russians, Venezuelans, Cubans, Haitians...
I lived in Japan and know many people in this situation. Most people just never tell the government and keep both. There's no proactive outreach by the government for these cases and it's ok unless you happen to mess up and produce your foreign passport when entering Japan instead of your Japanese passport. It's a "don't ask, don't tell situation".
There was a lawyer, originally from Japan, living in the US who did try to force clarity on this issue and sued the Japanese government. Unfortunately she lost so the status quo remains. https://www.asahi.com/ajw/articles/15077494
True, there may be complications if you travel to Japan from a 3rd country. It might be something they are aware of. I imagine most trips are directly from the other country of citizenship/residence.
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