Widespread recording and use in a cross-database is also a dragnet - its not one camera or cameras in a specific space, its cameras everywhere, accessible from anywhere, and its use constitutes a search (all IMO).

If you continue the argument that surveillance used to proactively rather than reactively find evidence is not a search, then with technology as it is today functionally there can be no expectation of privacy in public (somewhat fair) nor in private, given how widely distributed technology is - one could easily argue that technology's wide distribution is in part because of an expectation of privacy.

There must be a line for which people can expect privacy, or else privacy cannot exist. Its a fundamental value of liberty.