It's partly in response to the increased divorce rate, but probably more due to dating services, which make people comfortable with filling in questionnaires and looking at compatibility issues. It's not enough to be a relatively content, but habit-ridden couple. I think it's two people who can be happy and also creative together. That's what I would look for in a long-term relationship. Most of the questions derive from academic research findings about long-term success and failure in marriage and human relationships.
Spiritual compatibility is as important as any other.
It's difficult for a very spiritual person to be married to an atheist and vice versa. A lot of religions, such as Judaism and Catholicism, want couples to be of the same religion, which is itself a compatibility test of a very simple kind. I know who insists on pre-marriage preparations including a questionnaire like this one. They're mostly people on the Internet. Our Global Ideas Bank gets about 3.5 million hits a year, and the relationship section is one of its most popular parts.