I don't know if you are asking me or if this is rhetorical, but since we all like to blather on apparently, I'll assume the latter .Do helmets provide or not provide some rudimentary protection within their design parameters for people who might engage the protective abilities as tested?
If you are asking me, then yes, I think so. My argument has always been simply that the protection they provide is much less than the general public may think (including cyclists), and that I personally feel that most adults doing general purpose riding probably stand to gain relatively little-to-nothing. And I do think it is a bit logically inconsistent to wear one for riding but not jogging or running. But ultimately, it can be useful in some situations (as I've noted before, I wear one during slippery conditions (especially the first rain in dry Fresno, when all the oil in the road surfaces)) knowing that it probably won't save my life, but might save me a few stitches in a situation where I'm much more likely to go down.
My real concern though is simply educating about what they can and can't do; past that, I don't really care all that much if someone thinks they need one, whether or not they do in reality. Who am I to judge? As long as they don't try to nag me for wearing one, I'm OK with it (I'm even OK with people mentioning it... I realize they are concerned for my safety. But once I've said "no thanks" they need to lay off )