Wow...as someone who has almost always worked remotely, yeah, I dig it. Never thought of this before, but that's great.
I do think there might be obstacles in getting it set up for the remote employee (is there an always on software on remote employees' laptops? do they get shipped a separate InstantPing hardware? would there be an expectation that if someone InstantPings you, you're automatically put into a video conference with them because you're in front of your machine? etc...)
That said, if you could get past those obstacles I think this would be a great idea to pursue. Spending minutes at a time getting a video chat set up is something I, and many other coworkers I've witnessed, have had to do plenty of times and it's frustrating. There definitely doesn't seem to be a good professional video solution for "hey let's quickly and easily sync up with Facetime-level ease." I attribute that to most vendors trying to be everything while focusing on group meetings, which invariably makes the start-the-conference phase of the video chat the most annoying.
Maybe take this software/hardware hybrid and put it in each conference room. You flick a switch, press a contact name (employee email address) and it just happens. Remote employees could get something like a small, 1080p webcam with a software that allows them to choose to be away by default (connection doesn't happen if someone InstantPings them). Then if they change status they and the partner automatically broadcast to each other without any need to do something once the "mothership" (conference room in office) InstantPings the remote webcam by email address. And both parties would have display on or an indication that they're present so neither can be "watched" with knowing. Integrate with SSO for Google/Microsoft/Slack and it could be a real timesaver.
I have utterly no domain knowledge here other than being a remote employee, so take this as uneducated enthusiasm. But if I felt this way and actually worked in the video conferencing space, I'd build it.