Imagine chewing gum is an unbelievably effective cause: it’s life-saving impact is many orders of magnitude higher than walking. If we want to maximise chewing gum to the fullest we cannot have any distractions, not even potential or little ones. Walking has opportunity costs and prevents us from extremely super effective gum chewing.
This piece is about how those resources can be collectively deployed most effectively, which is a different question from “how can I do the most good.”
Michael’s post still applies. Collective resources are just a sum of many individuals and everyone/every group contemplating their marginal impact ideally includes other EAs’ work in their considerations. The opportunity cost bit applies both to individuals and groups (or the entire movement)
Any unit EA resource spent by x people has opportunity costs.
There is no need for a more diverse portfolio. There is no evidence to suggest that there are causes higher in expected value than are being worked on. If anything, the most effective way to maximise the EA portfolio is by doing cause prioritisation research, but this already is one of the most impactful causes.
People have different values and draw different conclusions from evidence, but this is hardly an argument for branching out to further causes most people agree there is little high impact evidence for.
If it were conclusively determined (unrealistic) that X (in this case AI) is better than Y (in this case animals), then yes everyone who can should switch, since that would increase their marginal impact.