It's been a year, but I finally wrote up my critique of "longtermism" (of the Bostrom / Toby Ord variety) in some detail. I explain why this ideology could be extremely dangerous -- a claim that, it seems, some others in the community have picked up on recently (which is very encouraging). The book is on Medium here and PDF/EPUB versions can be downloaded here.
Worth highlighting the passage that the "mere ripples" in the title refers to for those skimming the comments: