Good afternoon. Why can't the structured binding pack be used outside of
the template, whereas the expansion statement can. It seems to me that for
tuple-like types there is no significant difference between these language
features, but to use the first one, you have to use a synthetic template
where there is no real one. Is this a language defect?

I'm not sure what the documents say about this. I am writing immediately
after observing the error on goldbolt.

Thank you for your attention.
Artyom Kolpakov