I'm a BPhil student in Philosophy at the University of Oxford. I am currently thinking about getting into policy.
Pretty late to the party, but here are some thoughts.
I think one point that Amia might be making is a criticism of EA's culture. Amia seems to think that EA has a pro-political-status-quo culture. While EA people seem to share a number of basic assumptions about the world, an account of 'how power works' (that Amia would find acceptable) is not one of them. There is no prevailing attitude that capitalist political institutions are the root cause of a number of the world's most serious problems. Given Amia's political commitments, I think her view is that a prerequisite to driving morally valuable systemic change is the epistemic task of accepting a world view that has been advocated by socialist, feminist, and anti-racist scholars. It is not that EA should place a greater focus on systematic change. Rather, EA doesn't seem to take the epistemic task seriously enough.
If this is right, then it represents an opportunity for improvement. A closely related argument has been made by Kissel (2017). (https://www.semanticscholar.org/paper/Effective-Altruism-and-Anti-Capitalism%3A-An-Attempt-Kissel/1bf6ec429a11ce12deee337e3e7a3c7eb38375f3). He writes: "... I think Effective Altruism will be less effective in realizing its own ends insofar as it fails to recognize that capitalism restricts the good we can do... I first argue that Effective Altruism and anti-capitalism are compatible in principle by looking at similarities between Effective Altruist theory and some Marxist writing. I then go on to show that the theoretic compatibility can be mirrored in practice... I conclude by suggesting that their reconciliation would lead to better outcomes from the perspective of a proponent of either view. In short, an “Anti-Capitalist Effective Altruism” is not just possible, it’s preferable."