MongoDB VERY CLEARLY warns you about the limitations of the 32-bit install when you spin it up. When I invoke mongod on my 32-bit development box, I get a nice big message:

  ** NOTE: when using MongoDB 32 bit, you are limited to about 2 gigabytes of data
  **       see http://blog.mongodb.org/post/137788967/32-bit-limitations for more

If you manage to miss that, it's your own fault. Combined with the fact that he was using an unstable development branch, he has absolutely zero room whatsoever to complain. He hit a documented limit and got less-than-friendly behavior on an unstable build of the software. Going nuclear over it is just silly, and makes him look inattentive and/or naive.