As a Japanese who has interacted with Christians, Jewish and Muslim people deeply, I’ve realized there’s the ultimate difference between monotheism and polytheism/animism, that have formed cultures and the way people think. Monotheism is based on the absolute God where everything has to be black and white, which makes sense thinking it was born in the harsh environment in the desert. Japan, on the other hand, the culture is mostly about ambiguity. I’m not saying which is good, but it’s just so different. From my perspective, I wouldn’t call Buddhism and Shintoism religion rather philosophy and spirituality. They might have some myths and rituals but are more about wisdom, realization and acceptance about, such as appreciation, greed, emptiness in life and everything is transient that nothing lasts forever. Sad but true
I feel so sorry that a lot of ALTs having a hard time. In my prefecture, I know an ALT hired after JET program and works as a coordinator for ALTs at education board. There are some techers hired at public IB schools with special teachers licence given by education board. In private schools or IB schools, you can see a lot of foreign teachers working full time. As you say, may be they need TESOL, teaching licence in their countries, degree of education or any qualifications.