I read this analysis last year about why Japan is so behind with EVs. The number of parts required is less then combustion and Japan's government is concerned about maintaining employment levels

This article talks about the filler jobs and how the economy is stuck in the past.

https://news.yahoo.com/japan-future-stuck-past-220130554.htm...

Annoyingly I can't find the source that went into why they are pushing EVs.

Edit: To be clear that was the hypothesis of the source and they presented evidence that the government that backed it, like stressing job creation and the importance of the automotive industry, but there wasn't a smoking gun.

I imagine that Japanese labor laws are a major motivator for Toyota. From what I have heard of Japanese labor laws, salaried employees in Japan appear to be guaranteed employment for life. The result is that Toyota will not be able to fire its employees even if their jobs become obsolete, so finding a solution that keeps those jobs from being made obsolete is extremely important for Toyota.