[kuhhk]

Counter-theory: a bot builder needs to test out his bot code, and used tweets about Bird Box movie as the test subject to shill for, hoping to drown amongst the other fans, rather than something that might get flagged.

Seems just as plausible, if not more..

[SmellyGeekBoy]

Indeed, or the bots are just scraping the most popular content from the big meme accounts, which all seem to be sharing these Bird Box memes at the moment.