Makes sense from a business point of view. Why sell to create a new competitor with the same technology and an impregnable market base in the USA?

Better to force US competition to start from scratch.

Why don’t they just sell TikTok to a US Citizen who happens to believe TikTok should remain the same.

TikTok would remain exactly the same, with the exact same algorithms, but it would then be the free speech of a US Citizen so everyone would be happy. Maybe TikTok couldn’t send the data directly to China anymore, but they could certainly sell personal data on the shadowy data markets, just like every other US owned tech company does.

In short, why can’t China simply find a US Citizen or two to do their bidding?

This is part of Section H of H.R.815 that was signed into law:

(A) any of— (i) ByteDance, Ltd.; (ii) TikTok; (iii) a subsidiary of or a successor to an entity identified in clause (i) or (ii) that is controlled by a foreign adversary; or (iv) an entity owned or controlled, directly or indirectly, by an entity identified in clause (i), (ii), or (iii); or (B) a covered company that— (i) is controlled by a foreign adversary; and (ii) that is determined by the President to present a significant threat to the national security of the United States following the issuance of— (I) a public notice proposing such determination; and (II) a public report to Congress, submitted not less than 30 days before such determination, describing the specific national security concern involved and containing a classified annex and a description of what assets would need to be divested to execute a qualified divestiture. (4) FOREIGN ADVERSARY COUNTRY.—The term “foreign adversary country” means a country specified in section 4872(d)(2) of title 10, United States Code.

So, no, they don’t just get to change their name. They don’t get to change everything and still send data overseas to China. They have to cut ties with the CCP or else they cannot escape this.