Yes, I didn't originally know that (I thought constructors and exceptions would have been co-implemented and didn't consider that faillible ctors would have been outright impossible for a decade), and found out after pjc50's reply: https://news.ycombinator.com/item?id=33572348

I was going to say that such an alternative history C++ could have had MRVs earlier, or even sum types... but apparently exceptions were added a decade after constructors (if we draw that back to the original "C with classes").

So yeah, you're right that constructors led to exceptions, unless the designers of C++ had been willing to go back to the drawing board and entirely redo constructors.