"Why be 'taught' something that is NOT binding?"
All the Magisterial stuff is binding. These are, properly speaking, "teachings of the Church."
All the non-Magisterial stuff is non-binding. These are, properly speaking "not" teachings of the Church. Even if they are true.
(OK, it's a tautology, but it's as simple as I can make it.)
For instance: "Water is H2O. Its molecular mass is 18 g/mol, rounded to the nearest tenth." These are true statements. However they are not teachings of the Church. They are teachings of chemistry.
"The sound of waves can help calm you if you have anxiety problems, and can help you pray" --- even though it's related to spirituality, it's not Magisterial because it's an opinion or maybe a personal experience, or maybe even an observation of psychology.
However it's the type of observation that would not be out-of-place in in Encyclical. It's spiritually useful. But it's not binding.
It's not "binding" because it's not presented as a truth of faith or morals which must be accepted by all the faithful.
Only truths related to faith or morals are the proper objects of Magisterial teaching.
Does that help?