The German CPC6128 sported proper expansion ports and not mere PCB extensions. These were much more durable and they were implemented because of stricter German laws. Unfortunately this also meant that some peripherals would have a troubled time trying to connect to the back of the Schneider CPC6128s unless you got an adapter.
Would this mean that other manufacturers like Commodore and Atari had to enforce those same guideline for expansions!
In theory: Yes
But IANAL. As a matter of fact, the Schneider/Amstrad CPC464s sold in Germany never featured Centronics connectors, although the CPC464 was still sold after 1988, while the CPC6128 got the Centronics connectors in 1985.
Most probably a once issued regulative approval couldn't be revoked, so that the CPC464 could still feature cheap PCB connectors, while the new CPC6128, which came later, had to get better shielding due to changed regulative prerequisites.
This would also explain why the C64, Spectrums and so on sold in Germany had PCB connectors as well: They all started 1984 and earlier.