I didn't say it was the only rewarding thing you can do, but it's probably the most rewarding thing that is attainable for most people.

Don't get me wrong, I think the problem is multifaceted, but don't you think it's odd that in very disparate cultures they're practically all having the same issue, but only in places that have first world-type amenities? Yes, there are odd groups here and there that don't conform, but the trend to that affect is worldwide. And again, this is when we know our hormones are definitely getting disrupted.

"Personally as a male I don’t mind having kids but if I were a woman no way in hell would I have one."

I don't understand that. Why? If anything I've heard the opposite most of my life, where men are afraid to have kids for child support reasons.

In surveys, Orthodox Jewish women rate their happiness with life higher than secular women. You could argue that this is subjective, but I think you would find the same if you look at other derived markers, like substance abuse, suicide, etc.

There can be multiple reasons why modern societies have less kids, but the main theme of Orthodoxy is to keep as much as possible the same as in previous generations. So they would be avoiding almost all the possible reasons given for the decline.