Very odd for someone who is GC to not understand how important this is.
We're always being told by politicians and those with influence that both sides are as bad as each other — but we're not. GC people don't go round threatening people, trying to intimidate women who attend rallies, trying to prevent women from getting into buildings in order to hear other women speak and so on. It's good to have more evidence of the reality.
For years GC people have been pointing out that trying to insist that everyone addresses transpeople precisely as they wish to be addressed, even if that requires us to lie, is bonkers. You can't control the rest of the world's response to you and complain of being victimised and threatened with genocide if someone like this woman innocently uses a 'wrong' you don't like — which was actually the right word, because the other colleague was female and therefore traditionally referred to as a lady.
It also very clearly exposes the emotional fragility and lack of regulation that so many of us have encountered in our dealings with trans people. Many of us will have been screamed at in that way but don't have any evidence to show for it. So it's really important people see it.