If you get into a program and then realize that you’re wasting your time, you can always drop out of graduate school. If you’re deeply unhappy in graduate school but don’t want to drop out “because you’re the kind of person who completes academic courses” (ht Robert Miles), take a moment to consider what you value about your personal identity. Some super wonderful Effective Altruists dropped out of their Ph.D. programs and proceeded to have majorly positive impacts on the world (e.g. Katja Grace), so you can definitely be an über EA without a PhD. Remember, your goal should be to have a positive impact on the world, not to get some fancy letters after your name ;)
I finished my PhD, but it would have been reasonable for me to quit. I wrote a little bit about this here: https://forum.effectivealtruism.org/posts/rJ9LBoSt9MvXJrbEf/how-to-apply-for-a-phd
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