If all chinese phone maker dump Android, then the market share of non chinese phone maker like Samsung, Asus etc in international market will explode.
The decisive point doesnt belong to the phone makers, but to the established social platform on existing Android.
International consumers can switch from Google Apps to Hongmeng Apps easily if the Huawei Apps is better.
But international consumer CAN'T switch easily from Whassap, Facebook to alternatives offered by Hongmeng, because switching means disconnection from their own social network. Will you buy smartphone with Hongmeng but then cannot communicate with your friends, relatives and colleages because of no WA, also no FB?
China has to have social application established in international market first competing with existing ones.