It’s for voice, so that your mic is only active when you press an activation button. It’s how most PC games do it, and I would say it’s how most folks on PC use voice. It’s honestly a pretty basic feature, and super frustrating that it seems not to be a priority.
No you really shouldn’t have to be. They are responding in bad faith and distracting from the point of a serious conversation by um actuallying the fake sci-fi of a hypothetical.