Absolutely. To me this is clearly the case. One should be very hesitant to block the relationship with the grandparent.
...Seems to me that the lesson to be drawn from a book like this is not that laws are required, but...
My intent was to divide the two premises in the article: 1) That grandparents are valuable to the development of grandchildren, and 2) that laws and courts should enforce this. I agree that the second is not a lesson that should be drawn, but it is clearly implied by the tone of the article.
No argument there, although the legal example was set up with this line: "recent events suggest that not everyone takes the significance of grandparents for granted". This is vague enough that it's unclear whether the "not everyone" is meant to refer to the justices of the case in question, or the mother involved in the case. If the author was referring only to the mother (the circumstances in a celebrated court case illustrates how some people - like that mother - don't take the significance of grandparents for granted), then I have no problem with it. On the other hand, if there is some legal agenda being pushed here (which very well may be), I'm uncomfortable with that.
The most likely explanation is mere journalistic sloppiness which sees no difference between moral/wise imperatives and legalistic rulings :-) Maybe the author made no distinction between the two issues you delineate simply because the author doesn't/can't see them....
Best,