Thank you M.P. and Wu, that certainly helped me correct my
misunderstanding.

On Fri, 2026-03-13 at 09:30 +0000, M.P. wrote:
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> Whether the type of `t` is a forwarding reference would be taken into
> account during overload resolution for a call to the closure type's
> function call operator, at which point you're necessarily dealing
> with a
> specific instantiation of `var`, where `T&&` is a reference to a
> concrete type rather than a template parameter (and the function call
> operator is not a template).
>