Germany is not technically able to spy like that on the USA. The german agencies don't have direct access to american telefon lines and communication providers, and not to that amount of internet traffic, nor the technical equipment needed to search through data of that amount. And they don't have the rights to operate like that on american ground (in contrast to the rights the USA still have from after the war). There are american listening posts in Germany, not german listening posts in the USA.

Or do you think that if the BND asked the NSA to send over a few million of the collected emails from american citizens, they would happily do so? No, that is of course a one-sided thing.

The "of course they are spying on us" is FOX-rhetoric, and wrong.