Well, nobody from within effective altruism has written much up about this yet. It's not something I'm considering doing soon. Until someone does, I doubt others will think about it, so it's a non-issue. If some take this consideration for their careers seriously, then that's a problem they'll need to assess, hopefully publicly so feedback can be given. At any rate, you make a good point, so I won't go around encouraging people to do this willy-nilly, or something.

This seems like a case of privileging the hypothesis. Why should we have to show that early retirement + EA volunteering is superior to working a standard job and donating free cash flow, and not the other way around?