I installed a couple of these for some rich clients, back in the '90s. it was the latest great thing.
The picture quality was poor and the image lagged about fifteen seconds behind the voice.
The biggest weakness was that it transmitted on land lines — copper wire hard connected.
This was when cell phones were still primitive; anyone remember the 5 watt "bag phones"? Like carrying a lunch pail but oh they did transmit.
But, yeah, it was cool.
Ma Bell had a couple of Picturephones (at least the terminals - I seriously doubt that they were running the signal further than the back of the cabinets) at their pavilion at the '64 World's Fair in NY. I remember "chatting" with my then girlfriend over the demo.