Back when phone service and indoor plumbing were new, they were luxuries. The very rich had them and the poorer folks made due without. As time went on, more and more people became accustomed to life with these services. At some point, they shifted from being a luxury to being a utility. (Meaning that an average person was able to expect access to such a service at a reasonable rate.)
Broadband is still a luxury, IMO, but it is quickly moving to the utility stage. Many services are beginning to assume that you have high-speed Internet access. This, combined with the growing broadband-enabled population percentage, means that a person without broadband is going to be significantly "left behind" from society at large. I don't think we're quite at that point yet, but in a few years we just may be.
Incidentally, I'd qualify a "right" as something so essential to life that a person cannot be denied access to it and, in some cases, can't be charged for it. (Beyond what you pay in taxes if the government runs the service.)
Indoor plumbing has progressed far enough that it's a right. While you still might have some very rural areas without indoor plumbing, most do and it's virtually assumed to be present. Try selling a home in 99% of the country if said home doesn't have any indoor plumbing. ("A nice view of the city from your spacious outhouse."
) Broadband definitely hasn't progressed to the "right" stage yet.--