Comment by zahlman

It has been realized in the Python community for a very long time. But there have been years of debate over the contents and formatting, and years of trying to figure out how to convince authors and maintainers to do the necessary work on their end, and years of trying to make sure the ecosystem doesn't explode from trying to remove legacy support.

There are still separate forms of metadata for source packages and pre-compiled distributions. This is necessary because of all the weird idiosyncratic conditional logic that might be necessary in the metadata for platform-specific dependencies. Some projects are reduced to figuring out the final metadata at build time, while building on the user's machine, because that's the only way to find out enough about the user's machine to make everything work.

It really isn't as straightforward as you'd expect, largely because Python code commonly interfaces to compiled code in several different languages, and end users expect this to "just work", including on Windows where they don't have a compiler and might not know what that is.

See https://pypackaging-native.github.io/ for the general flavour of it.