No, that is not correct. Those telecasts are the property of the NFL. CBS cannot summarily choose an AFC team over an NFC one - by contract they are bound to carry the games in each team's primary and secondary markets. That means serving Giants fans as well as Jets fans. If the Giants are hosting the Broncos, guess what? CBS is bound by contract to show the game in the same parts of Giants' territory as Fox would - as well as in the usual markets where the Broncos are shown. Their contract is with the NFL and not with the AFC. Yes, they cover AFC games, but they must not play favorites in the case of an interconference game.
However, yesterday was a special case where one network (CBS) was faced with having to choose between two teams for which H/NH is a secondary market. A judgment call. A pick 'em. My contention is that they chose incorrectly.
On a different note, I'm going to call you out on this "poll" that shows more Patriots fans in the market than Giants fans. Sorry, but I do not and will not believe it until I see some backup for this statement. Personally, I do not think that this was ever true and, after the Pats jilted Hartford over the stadium deal (causing bad feelings), it certainly is not true.
Without a doubt, there are many more Giants fans than Pats fans in Litchfield and New Haven Counties. My guess is that the Giants fans outnumber Pats fans in Hartford and Middlesex Counties too, though it's more even. Only Tolland, Windham and New London Counties would be Pats territory. The Jets are a non-starter, it is the Giants that are at issue here.
And, of all people, channel 3's management should know better after being the home of the Giants for some 40+ years.