Given that in 2012 there was an entire IEEE magazine issue dedicated to her career and contributions to the field which really brought awareness of all her contributions...it's disappointing it took IBM so long to apologize, especially given they outed her circa ~2000.
That's a really nice thought. Having lived as a trans woman in the 90s, it does not match reality though.
Management is, always, a mixed bag. More and more managers indeed do not tolerate discrimination, but even in the face of policies, it exists. It certainly existed in the 90s, in very large patches.
As for corporate policies, IBM added theirs (gender identity specifically) in 2002. HP had GLEN in 1995 - "Gay, Lesbian, and Bisexual employee network". You'll note gender identity isn't part of that, though. (And bisexual is a silent B, I guess ;) If anybody knows when they included gender identity, I'd love to hear about it!
Before that, it was patchwork-y, and your best bet was finding a corner of the corporation that was supportive. And never raising your head to far, just in case. (Many of us did anyways, but more often than not, that had indeed the expected outcome)
Don't get me wrong, I'm happy and grateful HP & IBM were at the forefront of these policies. But it wasn't quite as easy a transition.
Talk is cheap.
We are truly an idiotic species sometimes.