One can not control the amount of or type of pigment in their skin and it holds no great bearing on most things sensible people would judge someone one and thus it is considered bad. Religious club is an interesting one, different to skin colour in concept and to an extent somewhat allowable, though what respect it gets varies wildly. To that end I guess it would technically fall under a certain definition of discrimination, though not really a negative one.
I do agree though that the public forum can not generally be expected to have only certain people come and that is kind of the whole point. Blogs have a measure of control but hey.
Anyway I am not sure what great insight will be gained from this if the sole qualification is... actually defining virginity is non trivial, which is surprising to some. Regardless I am not sure what there is to gain here as sex is hardly an enlightening experience and hardly a experience that clouds your judgement and closes certain avenues of great merit to you (assuming you are not a wizard in discworld I guess). I will attach no stigma to being one at any age really, and would also go so far as to say I find it quite sad that people would*, but at the same time this or the "opposite" seems like an especially pointless thing to be proud of.
*I guess it is part of life that many would consider important, and even comes to dominate a lot of their thinking and actions, but it is not like it is a particular reflection upon your moral or intellectual character.