Reddit reviews The Nature Fix: Why Nature Makes Us Happier, Healthier, and More Creative

There are probably three separate things that need to be distinguished there: (1) it's objectively important, (2) it is actually important to the parents, and (3) the parents can speak theology well enough to say why it's important to them.

For (1), it's possible that we're in a cultural moment where most people are oblivious to really important things. Every age has its blind spots. Christians certainly believe that this is true, at least the majority of us.

For (2), of course, church may not actually be important to the family, but they may need to appear like it's important for whatever reason. I think that a big chunk of the decline in church memberships is that fewer people feel this pressure. There have always been people who would go to church just because they felt like they ought to, for social or political (Soviet-related) reasons, and now just... don't.

For (3), to take a non-religious example, you don't need to be able to write a book - or even a paragraph - on how nature affects mental health to accept that going outside is important. There are certain things that you can only pick up on the importance of by experience.