>From [module.interface]

> An exported declaration that is not a module-import-declaration
> shall declare at least one name.

And specializations do not introduce a new name.

On Wed, Jun 2, 2021 at 3:01 AM Jason McKesson via Std-Proposals
<std-proposals_at_[hidden]> wrote:
>
> What makes you think that template specializations cannot be exported?
> I checked the modules and templates chapters of the standard, and I
> didn't see anything forbidding explicit template specializations from
> being exported.
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