As you said there are lot of factors responsible for this. I won't those that refuse to give birth to more kids these days. It is not easy raising child anymore especially if they are more than two. If the parents consider the huge sacrifice and financial aspect it involves then little are we going to award blame. Government has a lot to do in that regard. They can make a policy that will make it easy to raise kids by either subsidising babies stuff and support the parents to some extent. I also think the social setting is essential too. The way people see relationships these days is one another level. This is almost happenings all over the world. People now prefer to look for perfect partner on social and often end up being disappointed since online doesn't always translate to being real in the physical world.
The support in Finland for kids is pretty good - it doesn't help. Money isn't the issue, lifestyle is.