Earlier quoted context omitted.
If religion was a net negative, it wouldn't have survived for... well, since monkeys grew a rigid spine. The negatives tend to come from people exploiting others' dependency on its usefulness.
Everything has pros and cons, but some other behaviors that have survived for a really long time are murder, war, and (since it came up in this thread) alcoholism, which are not generally very well regarded. This isn’t to say religion is necessarily like those things, but it does indicate a flaw in the idea that behaviors that stick around mustn’t be so bad.
(Alcoholism has a massive component gifted to us by the genetic lottery, so it's really unfair to bundle it with these things.)