On GCC mailing list I notice email:
https://gcc.gnu.org/pipermail/gcc/2024-June/244252.html
Aside of misguided author (profanities & sending it to gcc instead of here)
some of his concerns could be valid.

Example: there is a freestanding version of the standard library module?
Or how to reduce blot that `import std;` can cause even if I only
use part of it like `std::vector` or `std::unique_ptr` but
I do not plan touching `std::regexp` or io.

Maybe something like `import std.core;` (like MSVC did) or
use import headers like `import <iostream>;`?

Or is this simply a QoI issue and the committee does not need to consider
how big is binary after `import std;`?