C23 would not be nearly as good as it is without proprietary C compiler extensions, and other non-C programming languages. Sure, C23's versions of some features are better than many proprietary implementations, but they wouldn't exist at all if the lessons hadn't been learned from that exploration.

Once upon a time, Jabber was the messaging protocol. But what killed interoperable instant messaging wasn't a shift away from Jabber: it was a shift away from interoperability. Requiring all chat communication systems to be Jabber wouldn't have helped, and it would have prevented IRCv3.