Obviously this is not the case at all in the android market.
Apple 44%
Samsung 16%
BBK Electronics 16% (Oppo/OnePlus/Realme 8%, Vivo 8%)
Xiaomi 8%
Others 16%
That's according to Counterpoint Research [1]
Profitability appears to be even more skewed in favour of Apple but I don't know the exact numbers.
It would be interesting to know what's included in that 16% others category as that's where any challengers would be coming from.
[1] https://www.counterpointresearch.com/global-smartphone-reven...
https://web.archive.org/web/20160423202414/http://www.dg.gov...
Unfortunately, I don't know what the authoritative source for company information is in China. It can't be blog posts and media reports I suppose.
Samsung is at about 35%, BBK is next at about 23% (Oppo+Vivo+Realme are subbrands of BBK as is Oneplus).
BBK is a bit the 'Luxottica of Android' if you will with several brands under them: https://en.wikipedia.org/wiki/BBK_Electronics
Plenty of other people care about market share (not to mention you're deliberately ignoring all the non-phone Android ecosystem that has established).