It seems that you believe China government helped local players succeed. That is not true in general. The private local Internet companies are not the government's child. They are mostly controlled by foreign investors.
Actually except Baidu vs. Google, you can not think out other examples the government made big impact. The other competitions in Internet between Yahoo vs. Sina, eBay/Amazon vs. Taobao/JD, MSN messenger vs. QQ, are all good counter-examples.
Foreign companies can not adapt to needs from local users. That is the key. The market is the king to decide the fates of Internet companies and products in China generally. Others are important but not critical.
And yet, all those companies do very well in HK, Singapore, Taiwan; aren't they Chinese also? Why is the mainland market so different from other smaller Chinese markets? They also do well in Indonesia, Thailand, Nepal, India...while the Chinese companies...they are just going to be stuck being local.
HK and Taiwan are too small market to have strong enough local team.
Supposedly, Chinese internet companies should do well in HK/Taiwan, these markets are definitely open to them, but since they don't have to compete with international brands in the mainland, they are not competitive enough to operate very well on the outside. Besides, any service run inside China is taboo outside of China (and Americans think the NSA is bad...).