"people should not face barriers to doing what they want to do on account of factors orthogonal to that goal"
What kind of factors count as "orthogonal to that goal"? If my goal is to become a physicist, say, does the fact that I'm not very intelligent count as an "orthogonal factor"? If the answer is no, then this is one form of my claim of them trying to make everyone as equal as possible even at the cost of making everyone worse off.
If the answer is yes, the question arises what they're objection is to some disciplines having demographics that differ from the general population. Given that they tend to take this as ipso facto evidence of racism/sexism/etc. this shows that denial of correlations between race/sex and other attributes is in fact much more central to their belief system then you seem to think.
BTW, the other form of my claim can be seen in the following situation: You need to choose between three candidates A, B and C for a position, you know that A is qualified and that one of B or C is also qualified (possibly slightly more qualified then A) but the other is extremely unqualified (as it happens B is the qualified one but you don't know that). However, for reasons beyond either A or B's control it is very hard to check which of B or C is the qualified one. Does hiring A, even though this is clearly unfair to B, count as "creating a barrier orthogonal to the goal"?
trying to make everyone as equal as possible even at the cost of making everyone worse off.
Could you talk a little more about/give an example of what you have in mind here?
A long blog post explains why the author, a feminist, is not comfortable with the rationalist community despite thinking it is "super cool and interesting". It's directed specifically at Yvain, but it's probably general enough to be of some interest here.
http://apophemi.wordpress.com/2014/01/04/why-im-not-on-the-rationalist-masterlist/
I'm not sure if I can summarize this fairly but the main thrust seems to be that we are overly willing to entertain offensive/taboo/hurtful ideas and this drives off many types of people. Here's a quote:
The author perceives a link between LW type open discourse and danger to minority groups. I'm not sure whether that's true or not. Take race. Many LWers are willing to entertain ideas about the existence and possible importance of average group differences in psychological traits. So, maybe LWers are racists. But they're racists who continually obsess over optimizing their philanthropic contributions to African charities. So, maybe not racists in a dangerous way?
An overly rosy view, perhaps, and I don't want to deny the reality of the blogger's experience. Clearly, the person is intelligent and attracted to some aspects of LW discourse while turned off by other aspects.