Fwiw, Matrix E2E actually exists in separate codebases in: Riot/Web, Riot/iOS, Riot/Android, nheko, matrix-python-sdk, libpurple (in PR), and shortly in Fractal (thanks to https://gitlab.gnome.org/jhaye/olm-rs etc). So yup, it sucks that it's not turned on by default in private rooms, but we're working away as fast as we can.
I love your project and am really looking forward to replacing a lot of stuff with Matrix-powered chat.
However, I strongly disagree with the author that Matrix should be recommended as a secure communication platform until E2E is stable (and, from what I understand about your project, you'll enable it by default as soon as you consider it stable enough).
my bad; i thought all the python ones had landed now. in practice the work is done.
Also, since writing this list yesterday, another client has got E2E running: Seaglass (a native Cocoa macOS client): https://neilalexander.eu/seaglass/
