[crazygringo]

That does, of course, export complete data, but the problem is you can't then import it, because that breaks the entire guarantee about not being able to edit past data.

[PixyMisa]

Ah. There is that.

They really need to create a workaround for that, because sooner or later you will need to migrate your data and right now it's simply impossible.

Edit: Particularly as, reading further, you cannot ALTER a temporal table. Which does make sense, but the problem remains.