Telegram just raising $1.7B in a crypto sale, which means it is the largest chat app not owned by a major corp or government. Plus familiar interface to Whatsapp, they won't even know you switched them.
Not even counting the ICO, which is suspect in itself.
Where does that come from? Because from what I gather it's precisely the opposite: Telegram users in Russia and Iran are leveraging proxies (sometimes run by volunteers) to get around their nations filtering.
When you're using someone else's platform it all comes down to trust, and I'd rather trust an expat Russian that left his home country on grounds of being coerced into handing over user private information to his then nation's surveillance strike force and refused to bow down on that same nation's attempt to subvert his new platform then blocking half of the Internet's servers, than an app claiming to be end-to-end encrypted under the helm of a company that has time and time again been caught red-handed invading everyone's privacy and lying barefaced about it and whose monetisation and privacy strategy is denounced by the very founders of said chat app to the point of dropping everything on the floor and leaving said company.