Of course halacha responds (I think "changes" would be a poor choice of words here) to circumstance -- that's not the "chiddush" that makes the idea of abolishing the bracha of shelo asani isha controversial. Changes in metziyus often (but not always) prompt changes in din; different facts can lead to a different verdict / outcome. We know hefsed merubah, sha'as hedechak, b'makom eivah, etc. can also lead poskim to provide innovate solutions or to rely on views that otherwise might not be accepted.
The with respect to shelo asani isha is simple: Do we have a right to invoke sha'as hadechak k'dieved dami not in response to an external change of circumstance, facts, or extraordinary need, but instead in response to our own feelings and moral judgments as to what halacha should or should not be?
None of what has been written on the topic (e.g. here, here, here, and here) provides any evidence that that question can and should be answered affirmatively. Case closed.
In Professor Tabory's paper on shelo asani isha (found on the JOFA website), he cites an array of commentators who have explained the bracha of she'lo asani in ways that do not demean women. Sensitivity to the potential (mis)interpretation of the bracha as offensive is not a new phenomenon. Historically speaking, Professor Tabory notes that, "...Orthodox Judaism found only one proponent for a change in the liturgy..." Only one! And the footnotes to the paper reveal that even that one proposal for change was made in response to the particular situation of eivah created by shelo asani aku"m, not in response to shelo asani isha.
With respect to halachic innovation, the dean of YCT, R' Avi Weiss, elsewhere (Judaism, 1997) has written, "...All those who hold to Orthodoxy contend that "new Halakha," which emerges constantly from the wellspring of the halakhic process, must always be based on the highest caliber of religio-legal authority. There must be an exceptional halakhic personality (italics mine) who affirms the new ruling on the grounds of sound halakhic reasoning."
It's a shame his musmakhim and talmidim have not adopted their rebbe's standard. Rabbi Dov Linzer notices that even Rav Henkin, a favored posek within the modern community, often will lay out theoretical approaches that allow great room for leniency, but then pull back from actually allowing more radical ideas to be accepted l'ma'aseh. Instead of ascribing this caution to a fear of "loss of credibility or acceptance," (link, p. 8), perhaps it should better be ascribed to yiras shamayim and respect for mesorah, values that are at least as important as fostering gender equality.
The burden of proof rests on those who clamor for change. Their subjective sense that the explanations of others, among them gedolei haAchronim, are lacking (mere "apologetics"), is far from sufficient.
I don't really understand why this issue has gotten so much play when there is so little to discuss.