These are mostly softballs though...1-at-a-time:
"I can saturate a 100mbps connection by booting a diskless computer. Why shouldn't our operating systems/environments be stored "in the cloud"?"
Clouds go down, your computer goes down. There's no compelling reason to put the OS "in the cloud". Your data? Maybe, if you can handle not having access to it every second of the day. And even today, one can RDP or VNC perfectly comfortably on a 20Mbps connection provided all the "cloudy" parts of the internet behave. More importantly, if the server and the links between you and the server aren't capable of giving you 100mbps then you can't saturate the connection.
"Why shouldn't I have more than one computer in my house?"
How does not having a 1Gbps internet connection prevent this?
"Remind me again why I can't have cameras all over my house and see them all at once while somewhere else."
Why can't you do that today? Streaming 1080p from x-number of cameras, multiplexed into a single display that's probably no better than 1080p is silly. The proper approach, regardless of bandwidth, is to downsample the displays before multiplexing at the broadcast side. Then you're just streaming a single video stream anyways, which is perfectly doable at 20Mbps.
"Why shouldn't I be able to speak to an SO wondering around the house doing chores while I'm in a hotel room?"
Again, why can't you do that today? There's no reason to stream video from empty parts of the house. In your use-case, you're only sending one or two video streams at a time anyway...again still healthily within the realm of 20Mpbs.
"All that aside, think of the games and entertainment that can be enabled. TVs are large enough to be almost life size now. Why shouldn't I be able to stand in front of one with a doctor or Amazon employee on the other side being able to examine each other, products, packaging etc in high resolution detail. (Note 1080 is not even close to high resolution for life size.)"
This is the only compelling case you've provided I think, but bandwidth is not the principle problem in this use-case. Everything from cameras to encoders to compressors to display devices are a bigger problem in this case.
And yes, you'll have to compress even at 1gbps. A 1920x1080 display with 24bit color at 60fps is something like 3GigaBytes per second or around 24gbps.
The next gen of TV is likely to be some variant of super hi-vision which is 7680x4320. @24bit and 60fps that's just shy of 48Gigabytes per second uncompressed or 384gbps.
So yeah, bandwidth will be a bottleneck in those applications, but 1gbps is not even close to handling it and I'm guessing the hardware required to real-time encode and compress video for a stream like that is astronomical.