And the "software is free speech" argument itself doesn't apply when we are talking about something malicious that is installing keyloggers and transferring private data to overseas servers.
I think it still applies even to "malware". It's just irrelevant. I don't understand GP's argument here either.
TikTok is not an American citizen. Nobody is preventing American citizens from printing the source code of TikTok on their tshirts so that people can compile it and use it. This is the only conceivable scenario where the 1st amendment would apply.
And even if that was happening, the US could rightfully ban use of Chinese owned servers in the US. Then we'd get what happens in China: a US-owned entity forms to run TikTok in the US. It is now subject to US rules and regulations etc.
And the "software is free speech" argument itself doesn't apply when we are talking about something malicious that is installing keyloggers and transferring private data to overseas servers.