While I tend to agree with your overall point, I was asking the question for a different reason.
I find it useful to examine my opinions from different perspectives, even ones I disagree with, in order to better understand the crux of the issue.
Again, while I personally agree with what you say, I think it's a bit assertive to say "proactive mass surveillance does not work". I know several people who would argue just as strongly that their work is critical to national security.
This is a bit nitpicky on my part, but your statement "as long as there is zero benefit it seems pointless" is a tautology. I think the argument is regarding whether there is zero benefit.
Again, I don't mean to criticize your beliefs; I'm just interested in openly exploring different perspectives to try and understand the situation better.