Earlier quoted context omitted.
While I respect your opinion I don't agree. First of all PRISM was not purely "a system for handling paperwork for lawful intercepts", see [0]. Second your assertion assumes that somehow all requests within these programs abided by "lawful purpose", which we also know is not true. Whether FISA rubber stamps were lawful is subjective and your opinion but not fact. Your answer purports a black and white perspective on…
It's not a 'just your opinion, man' sort of thing - more or less nobody seems to have thought PRISM was unlawful. Rand Paul, I think, made some noises about suing at the time and eventually did file some sort of suit that ended up not being about PRISM.
[0] https://www.theregister.co.uk/2016/04/20/public_advocate_fbi...
[1] https://www.aclu.org/blog/national-security/privacy-and-surv...
Just because it was never settled that way doesn't change the history of it.