Encyclicals are binding? I think not!
Humani Generis, Pope Pius XII
There are most definitely parts of LS which deal directly with faith and morals, and constitute a part of the Church's magisterial teachings.
However, less than half of this particular encyclical deals with "faith and morals" and therefore less than half of it is part of the magisterium. More than half of it deals with prudential judgments, the physical sciences, the social sciences, public policy proposals, and other non-Magisterial material.
I don't blame anyone for being confused.
The encyclical itself states, more than once, by way of a disclaimer, that the Church has not got the authority nor the intention of replacing science and politics. Amen to that, brother./
Nevertheless, I think it was a kind of category error on the part of the Pope to lard so much non-magisterial material in there, to begin with.
Therefore; they are a waste of time.