When I first heard of effective altruism, the idea caught on immediately and I sought out more resources. Not long after I was an enthusiastic effective altruist. The concept of doing great things inspired me and I soaked up the contents that the EA-Community provided. I then also joined a local EA Group (this post is anonymous in order to protect their privacy). Whilst I only have experienced this one local group, the issues that I have observed likely extent to other groups and the EA-Movement in general, especially since they are deeply rooted in most of the content provided among the EA-Community.
The single biggest issue (and the only one I am going to outline) that the EA-Movement faces, is lack of independent thought. Effective altruism is doing the most good you can. This very simple main idea provides the only axiom by which all actions are to be judged. I painfully experience that many, who call themselves effective altruists, do not rethink or judge their actions according to this axiom. Instead they turn to blueprints provided by EA-popular-culture. MacAskills book "Doing Good Better" is a perfect example. The book has not quite the same role for the EA-Movement as the bible has for Christians, but in this context I find the comparison to be on point. Both of which provide additional axioms for "how to be an effective altruist (or Christian)" that can not generally be derived from the very foundational "trying to the most good". The book describes, as many other resources do, what an effective altruist is like and which actions he pursues.
As with all dogmatic structures that drop from heavenly sources and are not inexplicable by pure reason, this leads to serious problems. Looking at the local EA-Group, I honestly can not remember any person in my life that is using his resources less effective than every single member of this group. I jokingly started calling them the "ineffective altruists of the city I live in" when I was talking about the group with my friends and family. And they do live up to their name. Like many local groups this one also receives small funds from the CEA, which are squandered of course for utterly useless purposes like distributing ugly flyers in the neighborhood, purchasing outdated and below average books or watching documentations on factory farming. Worst of all, our time is wasted. The weekly meetings are not filled with much content except for who gets to moderate next week (no one ever wants to). Somehow, these meetings do take 3 hours that could be used more effective doing literally anything else. It is safe to say that for the negative promotion alone, this local group is downright harmful. Most of the members live their lives according to doctrines that they believe are inherent with EA. This includes for example being vegan because it is seemingly obviously the logical and most effective way to improve the world we live in. The only doctrine that is unpopular (I wonder why) is donating to effective charities, although most members "know" that "donating 10%" (no more, no less) is what an effective altruist should do.
I think that the idea of effective altruism has huge potential and a social movement can help to promote the idea. But living our lives according to blueprints of "what a effective altruist is like" is extremely dangerous and potentially very harmful. I urge you to really think about how much good the actions you take do. As for me, I will continue to be a happy effective altruist. Therefore I see myself forced to let go off the by far most ineffective activity of the last months, interacting with the EA-movement.