Reddit will continue to highlight Weekly/Monthly Average Users to the press and advertisers, since those metrics won’t take much of a hit. You visit the site once to vote in a poll in favor of continuing the blackouts, you’ll get counted in those.

Those more granular metrics like session length and especially Total Posts Viewed are what really matter when you’re trying to run ads, and it’s hard to imagine a world in which those did not take a huge hit when most of the major subreddits are either blacked out, or (even better) flooding the front page with repetitive pictures of John Oliver.