If one offers you ice cream more often than the other, that doesn't make them "less bad". Chemotherapy is "less bad" than cancer, but most folks generally don't want to have either.
Both parties are self-serving.
Both parties have supported the surveillance state.
Both parties ignore their constituents when convenient.
Both parties have promoted legislation that they themselves are exempt from.
"Less bad" is a red herring. What's better, a shit sandwich or a sandwich with 90% less shit in it? Partisans will try to convince you that any sandwich will have shit in it, and their particular sandwich's shit is barely noticeable and actually good for you if you were smart enough to realize it.
But your systemic critique bypasses the obvious point that ideologically, there are great differences between the major American political parties on this issue.
Denouncing the system as "all shit" does nothing to change this fact.
Yes, the principle being: if the other guys are for it, we're against it. Just like the Republicans.
You can argue for individuals standing on principle, such as Ron Wyden (D-OR). But he was a standout in his own party when it came to re-authorizing the Patriot Act in 2011. Likewise, in the same party you have Dianne Feinstein (D-CA), who is a major proponent of mass surveillance.
No, the Democrats are not magically immune to corruption or self-service. There is no Democrat Exceptionalism here.
Also bringing up the Patriot act is dishonest, that's a national security issue, while this is a consumer privacy one. These types of things intersect, they're still different concepts and different bills.
A FISA warrant to get my information? Fine, I accept that. There's oversight and every nation needs security and has processes in place to ensure it, flawed as it is. Handing my info to every shady marketer and social media company? No.