Re: "speeds of 1Gbps"
Famous last words from many a person.
1Gbps may not be required 100% of the time but when you do on occasion need it and it is not there you wonder what you are paying for.
If we can (and we can) build the infrastructure to take more than that then we should. Let me use your above example with requirements now (not in the future) with that 78Mbps connection.
My wife and I usually watch the same programs (streamed) at 1080p which is enough for us at this time but 4K is starting to look like the future more and more. Services for this vary on their recommendations (and I can't be bothered to do the maths now) between 15Mbps and 25Mbps. I'll settle in the middle at 20Mbps.
Me and My Wife = 20Mbps, Daughter = 20Mbps, Son 1 = 20Mbps, Son 2 = 20Mbps, your 38Mbps is way too slow. If my wife and I want to watch separate programs then add another 20Mbps and I've already blown your 78Mbps. Yes it's not all the time but as I said when it's needed it's needed.
And 8K is here too. I see no need for it but higher and higher fidelity is the future so double that in a few years, again a few after that and you can see why we need the provision and I've not even touch on other uses aside from TV that gobble as much bandwidth as possible.
Let's actually build for the future for once rather than accepting second or third best. Do it once do it right, or am I too much of an optimist?