Those people don't get the point of Erlang. You'd have to be completely oblivious to complain about performance on the Erlang VM. The Erlang developers will always sacrifice performance and everything else in favor of reliability and response time. Consider that every actor has its own heap and GC. That's slightly absurd, honestly, but it makes sense when you think about Erlang's goals. I just get so frustrated when people say things like that.
Indeed, these claims always lack context of what is being attempted. If you are using Erlang to perform matrix multiplications on large datasets or some kind of CPU intensive work, you're probably barking up the wrong tree.
But if you want to parallelize and distribute less CPU intensive tasks and have fault tolerance, then it's a good choice.
