And that it uses a proprietary encryption protocol, "MTProto", which has been repeatedly found to have vulnerabilities, like every other self-made encryption scheme.
Now add in the fact that it's a UAE company...
Now add in the fact that it's a UAE company...
No, it has not. Recent research by seasoned encryption experts found minor bugs in realization, mostly around messages order. @see https://ethz.ch/en/news-and-events/eth-news/news/2021/07/fou...
Telegram's protocol might be custom, but it's well described and there are open source client implementations.
Whatsapp is totally closed and non-interoperable.
And whatsapp is made by an US company, that's an assurance for data collection and massive surveillance.
I don't know why you keep saying that. They have servers and offices distributed in different countries, but IIRC most of the team including the founder and CEO are Russian. They say the distribution is so that no single jurisdiction can force them to do too much.