Just tax TikTok. Make Americans pay money to subscribe to it. Apply the same principle to any other social media entity based in another country. It's that easy.
This isn't a "capitalism based harm" that tariffs are intended to fix, this is a "national security based harm" that's being targeted. You can debate the merits of whether or not TikTok is a threat to national security, but under the supposition that it is, tariffs are not the correct lever to pull.
So, it's not "that easy". I like the smugness though.
The US did not merely ban Huawei, it was part of a broader national security concern, where ZTE was also banned as part of the equation, and conceivably other major Chinese telecommunications firms with a strong enough foothold in the US would have been (or will be in the future) as well. Not to mention, use of TikTok is entirely an individual choice, a telephone network user does not choose (or have knowledge of) the origin of the devices their communications are transmitted through.