> Having the US's primary rival, which runs massive disinformation campaigns, also opaquely control the content that US youth consume en masse seems worse than...just about any alternative

How is it worse than making disseminating disinformation illegal? The law as written lays bare the true motivation - it's not about fighting disinformation ("inauthentic user activity" has been detected across all social networks for the purposes of disinformation). It almost certainly is about protecting American companies from competitors with better AI algorithms. The legislature has telegraphed that the tech/potential for abuse are not problems by themselves - ownership by a Chinese company is what they take issue with.