Domain-specific auctions was nice when it was done by Project Wonderful, but there is too much convenience in being able to push advertisements for the entire internet.

Designing secure APIs that can’t be misused by a Cambridge Analytica or similar is a hard problem. Google Plus was “breached”.

To be fair I'm not even sure which companies I trust to do ads with. I guess I'll avoid ads on any of my websites. I do agree though, security of that scale is not an easy problem to solve.

Project Wonderful is the only ad network I have ever fully whitelisted. I've whitelisted specific networks on specific sites before, but Project Wonderful was not only acceptable to me, I actually occasionally found it useful on the webcomics I saw ads on, as it generally showed off the art style. I (almost) never saw ads for unrelated products, there were no videos, few ads were even animated. To me, Project Wonderful fulfilled the promise of 'relevant advertising' far more than the tracking ads currently do. General location- and demographic-targeted advertising can certainly be annoying, but is not offensive in the manner of tracking my browser history.

I just hope ALPR/facial recognition/etc doesn't get combined with digital billboards to bring internet ads into physical locations.