Why would someone who has stood up to the Russian government multiple times, had a company taken away from him already for not being compliant and is now living in exile hand control of Telegram to that same government?

Why are you assuming that Pavel is the only possible exploit that could be used to own Telegram?

because that is what they're implying when they say "controlled" by the kremlin

That's the cover story you see.

Why would such someone would wave flag of security making it the biggest selling point and then go with questionable practices?

Telegram being secure or not is a separate question.

Secure messaging is hard, most people when producing secure messaging will produce poor secure messaging - it doesn't mean they've been compromised by a government.

Yes but Telegram continues to avoid fixing flaws that have been pointed out by cryptographers.

It's one thing to get some security wrong because its "hard." It's another to not fix those problems when people explain how and why you did something wrong.

I guess they will fix those theoretical flaws when someone make real exploit?

RSA encryption is theoretically breakable by quantum computers, but people still use it and gonna be using it until someone break it.

"Probably the best-known test to see if someone was a witch was the swimming test Basically, if you found someone you suspected of being an old crone, you’d drag them to a pond and chuck them in. If they sank, they’re were innocent (and probably dead) but if they floated they were guilty…and quickly executed."

Russia, of course, has a long history of disinformation and propaganda. But it seems to me like there isn't a trust problem with Telegram right now, so why is the Kremlin throwing this charade if current targets are already using Telegram and trust it? Surely it would be in their interest to lie low and (supposedly) collect data through a backdoor than risk having their bluff called and being forced to ban it?

So that more activists will turn towards using Telegram actively.