I don't think that's true.  Entertainment has always addressed political issues.  This is no different.  Entertainment has also addressed various marketing issues.  After all this is America and the all mighty dollar reigns supreme.  I give the players many kudos for standing up (kneeling) for social justice issues.  The idea is to shed light on issues which most people would like to shun.  Only by doing this can effective change occur.  Whether fans return or not, who cares.  There are larger issues at work here.