If it's a conspiracy, what's the common goal? There's nothing in in for the companies involved. You might just as well say rape is a conspiracy between the rapist and the victim.
A conspiracy doesn't have to have a common goal between all parties. What kind of bizarro logic did you use to reach that conclusion? People and companies can conspire with others against their will, you know. E.g I blackmail you in order to conspire with me to steal valuable data from your employeer, etc.
The goals are set by the NSA, and the tech companies could not care less about them. The agree to conspire (ie. help the NSA) though, because there would be other consequences if they did not. From prosecution from the government, to under the table blackmail, etc.