It has been attempted at least at the OS level. COM and the much improved WinRT are one example (WinRT relies heavily on metadata), the Objective-C runtime on A

It has been attempted at least at the OS level. COM and the much improved WinRT are one example (WinRT relies heavily on metadata), the Objective-C runtime on Apple platforms is another (which instead accepts lots of dynamism). The problem is that OS vendors are the only ones with enough sway to force people to use these things, and even then just barely (the Rust WinRT support is developed by Microsoft themselves). The only entity with enough sway over every language in existence when it comes to supporting an ABI is, ironically, the C standards committee, because every language already talks C and needs to continue to do so.