I don't think it's accurate to say Biden is banning it. The vote in the House was very bipartisan. R's were like 92% in favor and D's more like 75%.
Yes: 155 D + 197 R
No: 50 D + 15 R
On Monday the White House clarified its position:
"We do not want to ban apps like TikTok. What we want – and what the
legislation we support would do – is ensure that TikTok becomes owned by an
American company so that our and our children's sensitive personal data stays
here instead of going to China and so that Americans' understandings and
views can't be manipulated by algorithms potentially controlled by the PRC."
so they want to outsource to nations where paucity of labor and environmental laws give corporations higher margins, but is ready to force a ban if US laws cannot control the narrative and influence people. Okay
Yeah, the White House doesn't pretend it's not about influencing public opinion. So it's a natural question, what opinion are they worried about. Maybe there's no particular one, but idk.
The bill gives the US President, currently Biden, the ability to designate social media apps as sufficiently popular and its owning nation as adversarial, mandating a forced sale. Biden approved the law and chose to use it on TikTok. So you could say it's to be sold or else banned (and China has already said they won't sell), but anyway it's in Biden's hands.