Excellent topic and also very appropriate to these times, and it is true that facial language is well used but treacherous, particularly happens to me that I express a lot with my face and it gives me away my thoughts, but well that must be handled.
On the other hand I must clarify that you say that it is a language understood by all, this is not so true, because there are people with lack of empathy and identification of these for example.
Thank you for your contribution