From another article from the New York Daily News in May of 1980:
In New York recently to confer, sip, promote, and quietly suggest, Twining had only kind remarks to make about Americans and tea. And why not? When coffee prices jumped in 1978, some of the committed caffeine audience switched to tea and sales have continued high ever since. This, along with what Twining terms our "increased sophistication" about the kinds and varieties of teas, have made us, if not a tea-crazed nation, a tea active country, potentially ready to drink even more. [. . . ] Although the teas vary, depending on the season and the crops, each blended batch must be consistent with the last and as much attention is paid to an Earl Grey, which averages $2.95 a pound [$9.49 in 2021], as is to a vintage Darjeeling, the rare "King of Teas," which retails for about $4 a pound [$12.86 in 2021]. Even at its most dear, however. Twining holds that tea is the most economical of drinks. "A pound of good tea," he said, "will make 240 cups, and a lot more if you like it weaker. When you cost it out, you see that it is the most reasonable drink in the world."
It looks like part of the context for the interest in tea was a sharp increase in the price of coffee in the late 1970s that shifted former coffee-drinkers over to cheaper teabags, I suppose then opening the opportunity to entice them with loose-leaf teas.
One thing that is hard to tell from just the newspaper articles is how much of "Mr. Twining" was a gimmick and how much was genuine. The newspaper articles seemed to play up his Britishisms, like in this 1981 article from the San Francisco Examiner:
Sam Twining has tea in the morning, tea at noon, at tea-time, tea in the evening, tea before retiring. He drinks the stuff with different foods and when he's in different moods. He even matches it to the weather. When it's really blistering outside, he'll pour a cup of hot Lapsang Souchong. "Because hot tea," he says, "has an extraordinary property that not only quenches your thirst but cools you down." When it's not so warm, he'll opt for a variety like Prince of Wales tea. And when it's one of those "really cold, horrible, wet English days," he'll turn to a potent potion like Assam. He averages nine to 12 cups of tea a day, but he doesn't consider himself hooked. [. . .] Twining is on a U.S. and Canadian tour to check out tea lounges in Four Seasons' hotels like the Clift in San Francisco. "I think tea-drinking is just catching on in the United States," he says. "It's becoming very popular among young Americans who have seen coffee as a Momma and Poppa drink. They want to break with tradition and have a beverage of their own." But Twining questions the form of the beverage. "To me." he says, "the worst crime of all on the American market is that something like 20 percent of the sales are of those bottles of iced-tea mix. I've checked, and only about four percent of the stuff is actually tea." Twining also has some other strong ideas about how tea should be enjoyed. "Being brought up as a Twining," he says, "I've never put sugar in my tea. Sugar takes away the delicate flavor. If you have to have a cup with sugar to get a pickup, fine, but don't consider it tea. Have one cup with sugar and then another cup straight. "Milk is all right, but if you use it, put it in the cup first and the tea second. If you add any small measure to a large measure it doesn't mix well. More important, the milk is usually not in perfect condition. If you add it to tea, it can separate, and you get revolting fatty globules." Even worse than revolting fatty globules is cream. Twining doesn't get upset when you ask him about the Boston Tea Party. His father did thorough research on that and found it wasn't Twining tea that got dumped into the harbor. But when you inquire about putting cream into tea, he looks aghast and says, "Oh, no. Much too heavy. Stick to milk."
"You Americans and your bottled tea", having a prepared answer in response to the Boston Tea Party, all seem a bit like someone who has been coached, most likely by someone from Ruth Morrison.
I suspect that part of the reason books and newspaper articles were so positive was due to the mismatch between his press reputation and his actual duties. Book authors always seemed stunned and flattered when he took time to answer their questions personally, often giving him personal thanks in the acknowledgments section, maybe not realizing that it was likely a large part of his role at Twinings to do just that while others ran the day-to-day of the company.
Someone seemed to have a real knack for detecting good photo opportunities as well. Want to promote Twinings Earl Grey? Why not get a photo of Mr. Twining with Richard Grey, the 6th Earl Grey, in front of the old Twinings building? Holding a teapot, as though we had caught them having tea right there in the street?