Earlier quoted context omitted.
Signal is probably the best combination of easy-to-use/secure.
Signal doesn't support vcard which makes it a non-starter for many people [0][1]. [0]: https://github.com/signalapp/Signal-Android/issues/6520#issu... [1]: https://github.com/signalapp/Signal-Android/issues/6520#issu...
And could you give an example story illustrating how two users would run into this issue in practice?