I know if you go back to December hardware sales threads from last year you can find some. I remember a specific post about how we might as well not track Chinese sales since they’re so low(or something like that lol). 

Aside from Nintendo titles not being offensive for Chinese government (which would ease their distribution) i think selling The Switch under the Tencent Umbrella also helped it alot, since its a household name there

I could see Sony and Microsoft soon having a similar Partnership with Tencent in that regard as well 

Niko estimates more than 1.3 million sold units this year in both legal and gray markets.
They mention that this is almost doubles the yearly combined estimates from PS4 and XBO.

China will be key to the Switch being the best selling console of all time. China will eat this system up and the Lite will likely be even more popular. Mobile gaming is stale for the most part and having a console experience that can be taken on the go is something new and exciting.

From my understanding, markets outside the usual 3 (North America, Europe, Japan) are nowhere near as lucrative due to a variety of reasons; from incomes being much lower (who cares that India has more than a billion people if only 30 million of those can afford video games), to piracy being rampant (partially due to incomes being lower) to harsh import duties or being forced to work with local importer companies (indeed, see how Nintendo is forced to work with Tencent instead of selling directly; though admittedly in China's particular case I am pretty sure that is something that all foreign companies are forced to do)

As for why China > India, it is simple; China has a much higher average income and more people play videogames there than in India. Just look at GDP per capita (admittedly inequality means that this doesn't tell the full story but it is a start):

India: 1877$ (comparable to countries like Mauritania, Angola or Venezuela)
China: 10839$ (comparable to countries like Russia, Bulgaria or Chile)

That is a very significant difference between the 2.

For what is worth one video games company actually did manage to make Brazil work back in the day. Pretty sure Sega consoles were insanely popular there, to a degree that wasn't seen anywhere else :P (the SMS in particular was notorious for bad numbers but selling a ton in Brazil)

Yup knew the Switch had potential in China. This will help push Switch to over 140 millions. Next year will be huge.

And people thought it was a bad idea

So Nintendo should buy SEGA to dominate Brazil, gotcha. Looking forward to Warhammer 3: Total War being a Switch exclusive game.

Tencent were the key here, as any foreign business finds out: you need a Chinese company to facilitate the business. I wonder whats their cut