Maybe, but I think effectively it really was the Declaration of Independence. It would take some time for independence to be effectually achieved, but consider a counter-timeline where we lost the war: the Declaration would be a minor footnote at best in British history (which it pretty much is) and also not the start of the history of the Union. It’s because we won that the United States of America is a meaningful idea to anyone.

The Articles of Confederation wouldn’t even be a footnote, just a dusty document in someone’s library, maybe, and the Constitution would never have been written.