What’s Hot on TikTok? Defending Its C.E.O.

The latest viral trend on TikTok is defending TikTok.

“Now is the time to fight the ban on TikTok,” read a caption of a TikTok video that was posted on Thursday about the app’s future. “#savetiktok #keeptiktok.”

“Do I believe TikTok should be banned? No,” Representative Alexandria Ocasio-Cortez, Democrat of New York, said on Friday in her first TikTok video, which netted more than 3.7 million views.

Other TikTok users shared video montages of the app’s chief executive, Shou Chew, to the tune of pop songs and applied the “fancam” treatment typically reserved for celebrities.

Across TikTok, users have in recent days leaped to the defense of the popular video app, which is owned by the Chinese company ByteDance. In hundreds of videos, they have argued that the app should not be banned in the United States over national security concerns, questioned why American social media apps aren’t facing similar scrutiny and expressed concerns that their First Amendment rights are under attack.

The outcry follows rising concerns from lawmakers and the Biden administration over whether TikTok provides sensitive data about American users to Chinese authorities. On Thursday, Mr. Chew appeared before Congress and was grilled for roughly five hours, with lawmakers questioning whether TikTok was spying on Americans on behalf of the Chinese government, endangering young people with toxic content and invading people’s privacy.

Mr. Chew said TikTok had a plan to protect American user data and denied that the Chinese government controlled ByteDance. But his answers were largely met with derision by lawmakers, fueling calls for TikTok to be banned entirely from Apple’s and Google’s app stores in the United States. The Biden administration has also pushed for TikTok to be separated from ByteDance through a sale, a move that China has opposed, or for it to try to strike an agreement with the U.S. government over data security concerns.

But on TikTok itself, lawmakers’ concerns landed with a thud.

“There needs to be an age limit on congressional positions bc this was so embarrassing,” one user wrote in the caption of a video posted on Friday.

Many were solidly against a TikTok ban in the United States. Doctors, self-defense experts, parenting influencers and others shared videos saying they were already researching ways to maintain access to the app even if it became banned and blamed Facebook and Google for the criticism.

The hashtag #TikTokBan had 1.7 billion views on Monday, up from 983 million on March 18.

Many TikTok users also rallied behind Mr. Chew, who is Singaporean. They highlighted lawmakers asking the executive yes or no questions and then interrupting him. They also portrayed Mr. Chew’s responses as wins against uninformed lawmakers, who sometimes posed basic questions about the internet.

And they made their displeasure known in their videos. Some users cut together older photos of Mr. Chew and clips from the hearing with viral TikTok songs, like Chris Brown’s “Under the Influence.” One user posted videos of the “Schitt’s Creek” character David Rose sighing and rolling his eyes to express disdain for lawmakers’ questions. One account shared a video of a young child responding to the clips with exasperation.

The response was probably what TikTok had hoped for. Mr. Chew, who has avoided the public eye for much of his tenure as chief executive, posted a video last week on TikTok’s main account and told American users that lawmakers “could take TikTok away from all 150 million of you.” He posted another video after the hearing, reiterating TikTok’s messages to lawmakers. Each video received more than 25 million views.

“It seems clear that much of America did not experience the hearing the same way many members of Congress and political insiders did,” Brooke Oberwetter, a spokeswoman for TikTok, said in a statement.

Mr. Chew’s messages were apparently taken to heart by some fans who posted on TikTok that they found him attractive. One video spliced photos of Mr. Chew to the beat of lyrics from the K-pop girl group New Jeans: “Oh my, oh my God, I was really hoping that he will come through.” The caption read, “Come through for us shou oppa,” referring to a Korean term for older men. It garnered more than 4.3 million views.

Others called Mr. Chew, 40, who is married with two children, a “zaddy,” a slang term that rhymes with “daddy” and refers to older, attractive men.

“If TikTok bad, why is he Fine???” one user posted in a video with three-million-plus views. “shou zi chew didn’t chew he devoured,” one comment, which had some 29,000 likes, said under another video supporting the TikTok chief executive.

Mr. Chew, who had fewer than 20,000 followers on his personal TikTok account on March 21, now has 557,000, according to Trendpop, a social media analytics firm.

TikTok users also mocked some of the questions from lawmakers. One target of their ire was Representative Richard Hudson, Republican of North Carolina, who asked Mr. Chew at last week’s hearing if TikTok “can access the home Wi-Fi network.” The exchange — including Mr. Chew’s puzzled response saying, “Only if the user turns on the Wi-Fi” — was shared in multiple posts.

One caption read, “We’re … not entirely sure … if Rep. Richard Hudson knows how TikTok OR WiFi works?” Another caption featured a series of wide-eyed blushing emojis.