there isn't really anything wrong with doing it in C++ nowadays as long as you don't use bleeding edge C++ stuff That's the whole point of the KDE doc I linked

there isn't really anything wrong with doing it in C++ nowadays as long as you don't use bleeding edge C++ stuff That's the whole point of the KDE doc I linked. It's not a reasonable strategy to use unrestricted C++, just like it's not a reasonable strategy to use unrestricted Rust. You actually have to design an ABI, not just rely on the compiler to do it for you. I thought there was a GNOME doc too, but I couldn't find it. The point remains: there are lots of things in C++ that people who care about stability don't use at their ABI boundaries.