Noah Masterson, a web marketing manager in Austin, Tex., is like the Marie Kondo of Twitter. He keeps it tidy. “I just unfollowed about 20 people to get down to an even 400,” he said. “It felt really good.”

For Mr. Masterson, 43, the value of social media is that it brings together all sorts of voices and opinions that he may not otherwise hear. But if he decides one voice is too shrill, too self-promotional or too dull, he will declutter. “It’s a party, and I get to select the guests,” he said. “I can just eject someone if they’re not being a good guest.”

Maggie Cassidy works at a nonprofit in Chicago and is similarly inclined to vote with her fingers.

“Unfollowing is the best,” said Ms. Cassidy, 31. “I think that social media is so pervasive in our everyday life that it can be easy to forget that it is entirely optional. You can get into a cycle of being irritated and not remember that you don’t have to participate.”

She recently unfollowed a political journalist on Twitter, not because she objected to his tweets, but because she didn’t like the vitriolic debates those tweets sometimes incited. “It got a little ugly over there,” she said, “and I didn’t have to participate. Anyone who seems to be using their Twitter handle to pick fights, I’m not interested.”