But what does a woman dress like?
"We talked about keeping my hair pulled back and wearing more neutral attire like the rest of the guys on the team. I took his advice: I traded my heels and Ann Taylor outfits for Gap khakis, button-down shirts and comfy Clarks."
And this basically tells us (us men anyway) absolutely nothing. It makes me wonder if the way you dressed was the problem factor and not so much the fact you wore womens clothing.
The reason I'm wondering is because when I look up 'Ann Taylor' or 'Ann Taylor outfits' I see a lot of outfits which I would describe as evening or party outfits and not so much outfits which are suited to wear when visiting clients who got regular IT problems. And with that I'm not focussing on the mini skirts and cleavages perse (but its something I do take into consideration), but simply the appearance itself.
I'm tempted to compare this with working at a department where everyone is casually dressed while I continuously show up wearing suits or similar which simply make me stand out from the rest. If you visit a client like that you'll get the same reactions, especially since they expected a regular IT guy to come over and fix their problems. Not some IT-manager-would-be, that might even give some people the impression that you're dressed like that in order to hide other things.
Which brings me to another issue; I don't know what kind of problems you and your team solved (you simply mention "regular problems") which is another issue. In more than one cases I had to crawl into places where the cleaners obviously never heard of in order to reach someone's computer, especially when the issues appeared to be hardware related.
I don't see people easily do that while wearing a suit, but I can also see women getting a huge problem with that when wearing something like a mini skirt.
Now, I'm not trying to argue that what happened to you isn't true or anything. The main problem with your story is that you wrote it with your own situation fully in mind. Resulting in several descriptions which tell the readers who weren't there absolutely nothing. When you say you wore "Ann Taylor outfits" then that doesn't tell me anything, and worse, perhaps my Google/Bing 'ing even gave me the wrong impression (as I mostly see women with mini skirts and often cleavages there).
But the thing is; I can easily see your story happening to a man as well.
It's not fully related, but when I switched jobs (years ago) from a consultancy firm (where wearing a suit was simply second nature (I always wore suits; in the office, at clients, it was an unwritten company policy)) to a regular service desk where everyone dressed casual I also started wearing suits, but after 2 days immediately realized that it might be a better idea to change my attire. Both the issue of standing out, but also from a team perspective; you don't want to give the first impression either that you feel to be better than the rest.
So I simply can't help wonder if something like that hasn't been going on here as well. Have you ever asked your co-workers or former manager about this? Because then you'd have the complete story, not one which is only based on personal impressions.