Grant Tinker, who produced “The Mary Tyler Moore Show” and other television hits in the 1970s and transformed NBC from a perennial ratings loser to a powerhouse of literate, sophisticated network programming that helped change America’s viewing habits in the ’80s, died on Monday at his home in Los Angeles. He was 90.

NBC confirmed the death on Wednesday.

To a generation whose tastes were shaped by the tube, Mr. Tinker was the unseen hand behind many of the most stylish, critically acclaimed sitcoms and dramas on television. He did it by giving his writers space to thrive, shielding them from those foolish studio and network executives who said they liked the story, all right, but wanted to change the boy to a dog — and usually got their way.

As president of MTM Enterprises, a company he founded with his second wife, Mary Tyler Moore, in 1970, Mr. Tinker produced the show named for her, one of the first series to feature an independent career woman as the central character, as well as spinoffs like “Rhoda” and the one-hour newsroom drama “Lou Grant,” which examined societal issues.