I think you believe that about secularists (whoever the heck they are) because you define "diversity" as including (or even celebrating) those who would discriminate against others based on some quality.  For example, when we are commenting on the cake bakers and the gay couple, you (or your identity at the time) wrote that you would be fine with a shop keeper discriminating against Christians or gays or Jews or blacks or whoever because, you know, freedom and honoring diversity. 

One can honor diversity but still push back against bigots.