I think the general concensus now is this is a result of history and now the interia of the existing code base and practices makes it implausible to switch. According to some, if Google were starting over now with C++ compilers and language standard at where it is now, likely exceptions would be permitted.

They're certainly not alone. LLVM has a prohibition on exceptions as well, for performance and binary size.

http://llvm.org/docs/CodingStandards.html#do-not-use-rtti-or...