My personal guess would be that a 2A plug with sturdy interior design would have been more than happy to carry 15A, after all the pins aren't much thinner than those of a Schuko plug. And unlike Swiss plugs (where I heard of that quite frequently) Schuko plugs are pretty unlikely to overheat and melt down unless the terminals inside are loose. Swiss and Italian 10A plugs as well as AS/NZ plugs seem to have the issue that the sheathing on the already rather thin pins (remember, Swiss and Italian pins are the same size as Euro plug pins but rated 10A instead of 2.5) reduces the cross section even further. In Italy this is even aggravated as the sockets are usually dual rated 10/16A, so the 10A plugs rely on the appliance limiting the current.
