It's the fault of built systems. CMake still doesn't support `import std` officially and undocumented things are done in the ecosystem [1]

But once it works and you setup the new stuff, having started a new CPP26 Project with modules now, it's kinda awesome. I'm certainly never going back. The big compilers are also retroactively adding `import std` to CPP20, so support is widening.

[1] https://gitlab.kitware.com/cmake/cmake/-/work_items/27706