This comment seems to assume very bad faith from the original poster (e.g. "these claims smell especially untrustworthy" and "I don't think these arguments are transparent."). These comments made certainly have very creative interpretations of the original post. 

I disagree with the following:

But I doubt you can make a case that’s robustly compelling and is widely agreed upon, enough to prevent the dynamics I worry about above.

"I doubt you can make a case that's robustly compelling..."

Systemic cascading effects and path dependency might be very coherent consequentialist frameworks & catchphrases to resolve a lot of your epistemic concerns (and this is something I want to explore further).

Naive consequentialism might incentivize you to lie to "do whatever it takes to do good", but the impacts of lying can cascade and affect the bedrock institutional culture and systems of a movement. On aggregate, these cascading (second-order) effects will make it more difficult for people to trust each other and work together in honest ways, making the moral calculus not worth it.

Furthermore, this might have a path-dependent effect, analogous to a significant/persistent/contingent effect, where choosing this path encodes certain values in the institution and makes it harder for other community values to arise in the future.

This similarly generalizes to most "overoptimization becomes illogical" problems. Naive consequentialism & low-integrity epistemics rarely make sense in the long run anyways, so it's just a matter of dispelling simplified, naive models of reality and coherently phrasing the importance of epistemics, diversity, and plurality through a consequentialist lens.

"...and is widely agreed upon."

Still relatively new to the community, so I might have the wrong view on this - but I'm always remarkably surprised by how openly EAs are willing to discuss flaws in the community & are concerned about solid epistemics within the community. 

E.g. recently just posted a submission to the EA criticism contest - and it's difficult for me to imagine any other subgroup which pours $100k into a contest seriously considering and rewarding internal & external criticism about its most fundamental values and community.