[Jiocus]

If he could produce substantial evidence to back up that claim, I'd be very interested in learning more. Until then, he doesn't have the credibility to be trusted.

Based on the assumptions I have about MEGA, Chinese intelligence and their motivations I find it unlikely they have an active, mutual conspiracy (impractical, expensive).

I assume MEGA is as viable target for covert, low-cost try-your-luck attacks as much as any other western infrastructure/enterprise. In that sense and in this post-Snowden world we live in, it seems as likely that any capable nation or five-eyes member et.c. could have* such a "backdoor".

*edit: 'has' → 'could have'