And who decides if the charities are effective? And even if they are effective, at what cost? Right now there are many charities that are dumping clothes on sub-Saharan Africa, and while those charities may be "effective" at clothing Africans they've also denied said Africans any chance at a native textile/fashion industry due to the dumping making such industries unprofitable. Is that a worthy trade?

What if two EAs making the same amount give the same 10% to two effective but opposing charities (say one donates to a charity promoting veganism and the other donates to a charity that provides free meals, including meat, to starving populations), is their altruism still effective or does it cancel out?

Like I said, it's "making the world a better place" 2.0. Better for whom? With what trade-offs? Well that seems to be up to the EA in question, with vague guiding principles of "be good, honest and focus on helping as many neglected people as possible" (https://www.effectivealtruism.org/articles/introduction-to-e...). Who decides who's being neglected? Can a group of people, say a subsistence farming community be considered "neglected" if they're satisfied with their lives, even if they're technically living in extreme poverty?

I could go on in detail, but reading that site's "values" is largely just a collection of left-wing-ish tropes where it's assumed the reader already knows what otherwise vague terms mean and agrees with their definitions. Which is ironic given Value 3:

  "Rather than starting with a commitment to a certain cause, community or approach, it’s important to consider many different ways to help and seek to find the best ones. This means putting serious time into deliberation and reflection on one’s beliefs, being constantly open and curious for new evidence and arguments, and being ready to change one’s views quite radically."

Even prescribing the 10%+ of income donated to charity, so? That's no different than a tithe. Only here you get to choose the church's values assuming you pick anything in the general direction of "good".

Ultimately it suffers from similar attempts to replace religion with secular humanism. The belief system is so abstract that, despite all the words it and its advocates spend describing itself, it doesn't really stand for anything more sophisticated than the lyrics to the Power Rangers Wild Force intro: https://www.youtube.com/watch?v=8Y3Ib0YNFaQ