. . a little bit ago started calling Google a dangerous monopoly, and urged people to use DuckDuckGo instead. A few days later he started calling Wikipedia a totally evil failed project. Then he started denouncing Google's new curator rules, and it's insane dependency on evil failed Wikipedia as a reference.

So, right about this time his Google search traffic dropped by 99%.

Seems Google/Wikipedia flagged his site as a "Possibly Dangerous Site", due to his rabid Anti-vaxer activities - and relegated him to page 36 and beyond.

His attack on Google's collusion with evil Wikipedia was definitely after the fact.

His calling Google a monopoly and to use DuckDuckGo was a few days before, but Google usually signals upcoming changes, and he has to have a serious crew of Web developers who would have been watching for hints - so I very seriously doubt this was a revenge thing.

Also, Mercola made no hint about it being a revenge thing, his attack was strictly against Wikipedia's biases.