That tends to happen with meta posts, especially those implying potential wrongdoing on the site. People just upvote them quickly.

This makes sense. It still seems suspicious to me.

If we're all going to post about vote conspiracies, maybe let's hypothesize that it was pushed by Lyft PR.

Unlikely. This type of incident would probably be considered negative PR for Lyft as well as Uber. Taxi bodies, Uber/Lyft customers, and those seeking to unearth stuff like this are probably the most motivated for this story.