Someone has to roll new crypto, otherwise we're stuck. That said, I know about the potential issues with Telegram's encryption.

You don't roll a new crypto and use it the day after, it must be tested for vulnerabilities, reviewed by expert cryptoanalysts.

It can take years, much like a car has to be crash tested, a new crypto algorithm must go through a certain process to be considered good enough.

AFAIK WhatsApps crypto isn't too old either but that doesn't seem to prevent HNs resident cryptospecialists from recommending it.

That said: I belive them when they say that WhatsApps crypto is stronger.

On the other hand I would expect them to leave a little note somewhere about WhatsApp being a data collection tool for Facebook that also still happens to works as an instant messaging platform.

Any flaws in Telegrams crypto that lead to decryption?

None discovered yet, just like my new design, this cardboard box on wheels I'd like to offer you as a replacement for your car.

Car comparisons aren't viable.