Why has digital cable changed that?!
Okay, let's go back. Originally cable was merely community antenna TV (CATV). Just a rebroadcast of OTA for people who didn't want an antenna or couldn't get good reception. CATV often brought channels from big cities to rural areas that didn't have their own channels or at least strong signal ones. The first recognized CATV system was in Mahoney City, PA, in the mountains northwest of Philadelphia and brought signal from Philadelphia. There was no basic, no premium. Everything was everything and the first systems were limited to channels 2 to 6, eventually to al VHF. I had cable of that type as a child.
Then HBO, the first premium to survive, came along. It was originally scrambled or on another frequency and required a box to tune it. Now we had two things. Basic, which was analog OTA and a premium (although those names didn't exist yet).
Then cable channels started. CNN, ESPN et al. (TBN may have been one if not the first.) Around that time, cable started putting channels on what we consider cable frequencies today, that is channels above 13 that are not UHF but many early systems stll stayed at 2 thru 13. Those that did not required cable tuners attached to your TV but when TVs started being able to get those channels, the tuner was not required for all but the premiums that started to exist. Still no tiers. Just what we consider basic plus premiums although I am not sure when the titles started. But it was all analog. Only the premiums required additional hardware.
Some premiums required a tuner box. Still using "odd" frequencies (that were often just high UHF) or scrambling techniques or (the cheapest method) line filters that removed a noise overlay on a channel like HBO or Home Team Sports (today's CSN Mid Atlantic) in Maryland.
So we had two clear things. Basic, which only required hardware if your TV could not tune the channels (pretty much 2 thru 64? and 94-99 on the cable "dial" but still analog and in the clear). And Premium, which required some sort of hardware at your outlet. Either a box or a filter. Premium also cost more. But other than the premiums, everyone paid the same amount and got the same thing.
Then came digital cable. Channels above 99. The advent of tiers. The start of blurring of the term "basic." Basic was not basic anymore. Basic was the analog channels below 99. Digital had channels above 99 that were not premiums. Typically things like the newer channels. MSNBC, CNBC, Fox News, Discovery. Many things you would call "basic" but were not. And this varied by system. Some companies moved things to digital that were on the analog portion. The digital tier (yes, they started using tiers) required hardware.
Of course, we have evolved even past that. Now pretty much everything is digital with the below 99 channels given a simple tuner box for older TVs but everything is addressable. So you get scattered channels and even non-premium add ons like the HD Pack from DirecTV (those are not considered premiums by anyone; they are just a pack of channels). Every system now has its own list of channels in different tiers. That is how you get channels on Fios's lowest real package not in the next one up. There is no such thing as basic on Fios (and with DirecTV's numerous packages, you can't define it there either).
But that is how digital changed things. Tiers rather than basic versus premium and addressable boxes and varied packages.
FWIW, when I googed "basic channel" the vast majority of hits were from Comcast as they still use the names Limited Basic (local OTA) and Extended Basic (for the 1 to 99 range) but I would be willing to bet that those names exist because of local regulation and laws requiring them to deliver certain service levels that were written years ago. Fios doesn't call its OTA only package basic. They call it Limited Prime or something like that.
When a term is not easily understood or does not have an agreed upon definition, it is worse than useless. The term basic channel is worse than useless.