An excellent query...Utilities are 99.9% an absolute necessity.
The internet / communications is at the same...but remove the communications (eMail and ? ) and its a luxury, IMO.
Enterprise that provides certain classes of services to the public, including common-carrier transportation (buses, airlines, railroads); telephone and telegraph services; power, heat and light; and community facilities for water and sanitation. In most countries such enterprises are state-owned and state-operated; in the U.S. they are mainly privately owned, but they operate under close regulation. Given the technology of production and distribution, they are considered natural monopolies, since the capital costs for such enterprises are large and the existence of competing or parallel systems would be inordinately expensive and wasteful. Government regulation in the U.S., particularly at the state level, aims to ensure safe operation, reasonable rates, and service on equal terms to all customers. Some states have experimented with deregulation of electricity and natural-gas operations to stimulate price reductions and improved service through competition, but the results have not been universally promising.
So while internet providers have largely supplanted/absorbed telephone (I believe nearly all telephone/cell voice/data is on the internet for interstate calls), they are not regulated (yet) to the same extent.
So yes, internet providers are a public utility.
Or what about the power plant. They need water, gas and phone service to operate. I guess electricity isn't a utility either.
You fabricated a completely arbitrary and absurd definition for utilities. Everything relies on everything else. The internet has become a core utility.
"If I take death into my life, acknowledge it, and face it squarely, I will free myself from the anxiety of death and the pettiness of life - and only then will I be free to become myself." ~ Martin Heidegger
The internet is a carrier for content, as are phone and TV. The difference is that the internet is at the place technologically where it can carry ALL that content making phone and TV superfluous.
Einstein, "science without religion is lame, religion without science is blind."