Nobody said it can’t help. But you’re making a bigger deal of it than it is. The effect is rather small. If you compare it to benefits from science such as having running water, heating, access to medication, etc. It’s not even on the same level.
Besides, not everyone’s mental health is helped by religion. As the studies shows, it’s only a portion of them. And a lot of people are miserable when religion is forced upon them.
Besides, weather or not religion helps with depression has absolutely nothing to do with science not being able to provide a sense of meaning. You’re simply arguing in bad faith here.