The problem is that Spectrum Voice service (and any other voice service that makes use of the Internet) goes down once the power to one part of the network loses power. While the network may be intact, there could be one pice of equipment on the network in your neighborhood which makes use of the same power that everyone else does. Most UPS's are not designed to keep equipment up for long periods of time - just enough so that computer user's can save their work and power down their computers.
POTS (Plain Old Telephone Service), which runs on pairs of copper wire, actually ran on large battery banks so that phone service would work independent of utility power. Home phones still work on this "Talk Battery" principle, and your cable modem / VOIP device will provide the talk battery and the current required to "ring" the phone, but not at the levels Ma Bell did.
If you want old-school land-line reliability, you may need to contact your local phone company and have them connect you. Expect to pay through the nose for this service, if available, compared to VOIP pricing. In addition, if the copper wire has been abandoned by the phone company (they've replaced it with fiber - like FIOS), you won't have the power-outage reliability that you had 30 years ago.
Maybe your complaint needs to be aimed at the local power company who cannot deliver electric service that meets your personal expectation for reliability. Spectrum is regulated by the NYS Public Utilities Commission. I don't know of any state regulatory authority that requires the cable or telephone companies to provide electric power for their residential customers when the electric utility itself is not able to do so.