I also use Simplex, but you see, a messaging app has the purpose of... messaging people.
Basically, no one uses Simplex (a part of a few selected chaps here on the forum).
There are a few outstanding apps out there (I like Keet.io very much), but if nobody uses them, there is no point.
I know what you are saying but once upon a time nobody used telegram, and before that nobody used viber, and before that nobody used skype, etc.
If you want to continue using telegram than you have to agree with their terms and accept all the risks. just keep inmind there is zero privacy with that app, and everything you wrote can be leaked one day.