My impression is that in some areas where discrimination might be more the way of the land, but you have agencies that are trying to adhere to a solid anti-discrimination policy that the folks will find ways to discriminate without getting caught. No facts to back that up, just a gut feel.
As I mentioned, I have a friend who taught college and came out while there. She had no real issues, and was seen as a woman by students and staff. Not in the most red state, but a conservative state nonetheless.
As for a story of how things are at my employer, here is an article published a few years ago featuring a very good friend of mine. https://news.3m.com/One-3Mer-Shares-Her-Experience-Transitioning-from-Male-to-Female And another good friend a year later. https://news.3m.com/One-3Mers-journey-of-coming-out-at-work-as-trans-and-disabled I figure that if the company wants to publicly promote this, they are certainly going to support us.
