It IS C++ though. All of the moc keywords are just macros (that the moc happens to interpret otherwise). signal: is just `#define signal public` and so on. You could compile annotated code without moc without issues.

Signal/slot connections are also compile-time type checked if you use the Qt 5 function pointer syntax: https://woboq.com/blog/new-signals-slots-syntax-in-qt5.html

I won't comment on the rest of what you say, as I don't really know enough about it.