He missed a point (and probably an important one for wechat's home market): CCP approval.
/snark
/snark
The team definitely needs to get the experience of being behind the great firewall. Try using a VPN there to watch YouTube, try using a locally purchased cell phone without access to Google Play or the Apple app store. Try bashing PRC government policies in WeChat.
Only then will they see how tightly things are locked down. It's not like they're the only ones to have this idea, so why doesn't it exist? Oh, because it's really difficult and even dangerous with the current police state that controls the communications.