That doesn't hold explanatory power in this case, look at the points, comments, and age. For "Modeling a Wealth Tax", "Canon's Cloud..." and "If founders treated...": https://www.dropbox.com/s/vk1i2q8mlbs5x2s/Screen%20Shot%2020...

I'm also suspicious, although most suspect as sibling comment to yours suggests, that it's likely something automated rather than malicious. Perhaps there's too few comments?