I’ve tried all of the apps you listed and they all have significantly less polished UX, except perhaps for Messenger. In an alternative universe, I could very well be using Messenger.
My personal assessment is that if you have to communicate something that must not ever leak out, you shouldn’t use a chat app at all, period — because in many many cases my interlocutor is less careful than I am (or their degree of carefulness is unknown). You can use an E2E video app but not a chat app. Telegram’s video is E2E.
If my entire Telegram history leaks out, I estimate that I’ll be in a bit of trouble, but not significant trouble.
Of course, I might be wrong. In fact, while writing this comment I realized that the risk is probably somewhat bigger than I think it is, and in an ideal world using E2E would be advisable.
However, this isn’t “why you should use Telegram” but rather “why do you use Telegram”, so this is why I use it — significantly better UX, partly network effect, and partly that leaking my entire history is not even in the top 100 worries I have in life.