I am just thinking more along the lines of - other than times where a computer is not available to us, why do we keep using traditional notion/pen and paper at all?

If everything is digitalized no one will have mark homework ever again.

I guess intros based on the structure of mathlib could work for people who haven't published their own textbooks.

I don't think many people are going to read Rudin (etc.) then try to rewrite the book or do the exercises in Lean by themselves or read through the mathlib files to see how everything is defined/proved in full generality.

Like a lot of people (I imagine), I'm not a professional mathematician working on advanced, complex problems but I would like to have the ability to have the computer check my solutions to exercises and maybe even aid me with hints for tackling problems if needed.

If math textbooks gave free use for people to rewrite them into computer format and post online it would make life a lot easier.

And they know they'll be facing allegations themselves for helping to enable the situation.

I thought it was the USA that makes these decisions

Don't even expect the drinks after work culture, a lot of that has disappeared. It was a thing when people actually had hopes that showing loyalty to a company would improve their lives.

If you want to enjoy life just watch videos of expats chilling in places Thailand for inspiration. Otherwise you may become like the Japanese people and end up bored and wanting to leave.

Most Japanese people aren't going to be any less apathetic about a foreigner than others of their own group. Naturally there will be more traction with those looking for free English teachers and gaijin hunters. What a larger proportion of people likes is money and entertainment. Not so much foreigners trying to be Japanese. A foreigner giving such vibes will always be lower down in social status than the natives.

It is unrealistic for the average person in the country to become fluent in English reading/writing - lots of people are barely literate in their original language. Even if everyone became more skilled and wealthier, what would that achieve? Import more junk from overseas? Increased wealth will just be funneled into land or spent on smartphone games and prostitutes.

Deep insights in finance are typically not useful once everyone knows about them.