That is backwards. Nearly everything in the web platform began as a proprietary extension, including JavaScript and XHR. Standardizing something that has never

That is backwards. Nearly everything in the web platform began as a proprietary extension, including JavaScript and XHR. Standardizing something that has never been used in real life is a bad idea. Convincing the other browser vendors to implement your new idea is usually impossible. So insisting that only standards ever be used would result in no progress at all.