This is an egoistical viewpoint, but if I want 8 bits in a byte I have plenty of choices anyway - Zig, Rust, D, you name it.
Should the need for another byte width come up, either for past or future architectures C and C++ are my only practical choice.
Sure, it is selfish to expect C and C++ do the dirty work, while more modern languages get away skimping on it. On the other hand I think especially C++ is doing itself a disservice trying to become a kind of half-baked Rust.