For those interested: In the US, you can't just take a test to become an electrician. You must first have a certified mentor or go to school, and have 8,000 hours of on-the-job experience and take 720 hours of instruction related to electronics.
In Canada a license is not required to DIY the electricsl in your house. To be all on board though, you will need permits for serious work, like replacing breaker panels for example. My son is a journeyman electrician (red seal). It takes four years with several weeks in the classroom per level, and on the job training. Exams written for each level, and an exam to become a red seal. I'm lucky because he does all the electrical work in my house! Most importantly, it is done correctly!😁
I think the one tricky thing about Japanese wiring is they don't have ground lines on most sockets or appliances and this can prevent a whole host of issues. These days with circuit breakers, GFCI, and even AFCI, electrical fires in the US are a lot rarer than in the 70s.
The US is moving to those crimp connectors as well but I've seen seem some reports they don't handle loads as well. Given the contact inside the connector is much smaller than the screw cap kinds I suspect if you don't crimp them properly you'll have too much current through too small a area.
