Yup. A VOX (something I’m familiar with from ham radio) is essentially the same thing as a gate (something I’m familiar with from guitar effects processing).
In the case of a VOX on a radio, it actually switches the function of the transceiver from Receive to Transmit when the mic level rises above a configured (usually a “VOX Sensitivity” knob) threshold, and then back to Receive when you stop speaking.
In the case of a Gate, the audio path is still ON all the time (and HighFidelity audio is full-duplex anyway), but your mic’s audio is muted until the level rises above a configurable threshold.
I would argue that a Gate is an essential component of a VOX, but the converse is not also true.
Now, with all that blathering and history behind us, if I wanted this functionality, I would add it externally. I have various audio plugins, apps, and even physical equipment in my bin of crap and wires… I could insert an analog (delay-less) or digital (slight latency, but only on my outgoing signal). I may very well experiment with that, 'cuz now you have me curious. And - it’s an area where I have some expertise (not true of Blender and whatnot).
It does make me wonder if things like NyQuist plugins can be somehow affixed to Interface and/or to the mixer part of the domain-server. I suspect something like that is already supported (haven’t gone searching yet), since reverb can be applied to audio zones of one’s domain-server configs. I wouldn’t presume to try to adjust a gate that would apply to everybody visiting a domain, except as a silly experiment. Your ambient noise floor is surely different from mine, etc.
In any event, thanks for raising a fun (for me) subject.