Or, at the very, least a rule that a proposed feature should be a vendor-specific extension for at least 5 years, and the vendor has to dogfood it in their toolchain.
Vendor specific extensions never get widespread use. Nearly everybody wants the ability to build their code with whatever compiler their customer has. There are a few exceptions who will use a vendor specific extension (microsoft), but the majority get scared that they depend on something that limits the future and so won't use it.
Internal use only is helpful but doesn't get the feature used, and too often leaves things not useful for a toolchain but useful elsewhere out.
Internal use only is helpful but doesn't get the feature used, and too often leaves things not useful for a toolchain but useful elsewhere out.