One of the problems I face when somebody comes along and tells me that they're now on Telegram, Cryptocat, Wire, or whathaveyou is that I might recall an issue but there doesn't seem to be a good up-to-date overview that answers the questions (1) should I trust these people (how bad was it; was it in their code or a dependency?) and (2) is it known to be far less secure than it advertises? (still?)

I recall e.g. that Moxie reviewed Telegram's security, found that none of it made any sense and that its authors didn't know what they were doing. https://tobtu.com/decryptocat.php looks like the cryptocat analogue of that. Have the two projects improved somehow? Have some people joined or others left?

Could you please also provide links for the claim that CryptoCat and Telegram are being used by governments to hunt down activists?