What’s stopping you from using multiple apps? You can probably convince most of your family and tech-savvy friends to download Signal/Jami/Keybase/whatever you might prefer.
No need to cut off people or uninstall insecure apps like Instagram to get to enjoy the benefits of communicating securely with some (rather than none) of your contacts.
I don’t think I’ve ever met a person who had less than 3 chat apps, and I can’t really relate to not remembering which contacts use which apps. Also, is a 50-100MB chat app really an issue when you have a 32+GB device? Even if only 1 person was willing to switch then I’d argue it’s a very small price to pay. Especially when the alternative is supporting an evil corporation that violate people’s privacy.
As for centralized logs, I would like for that as well, and I think something like Volt would be our best bet.
No need to cut off people or uninstall insecure apps like Instagram to get to enjoy the benefits of communicating securely with some (rather than none) of your contacts.