I'm pretty sure an empty social media account is more suspicious than no social media at all. Remaining silent may not be your best option.

Also, as a foreigner, it doesn't really matter what rights you may or may not have when people at the border have broad power to reject your attempted entry. Unless you're willing to try a legal battle, you'll be forever marked as "refused entry" in the US government systems, which is one of the many flags you need to clear to even get a VISA. I wouldn't trust the country that deports legal immigrants or just plain citizens without due process to care much about your right to remain silent.

I think it's been pretty well-known that the US government will track your social media activity by any means it can anyway. Setting everything to public makes it easier for the courts (after all, no need to admit to secret spying when everything is set to public) but I think it'd be an illusion to think the government doesn't have access to this data anyway. Or perhaps this is just a grift so more private companies can start scraping social media as a business model around immigration control.

The most interesting change here is that they're targeting people criticizing Israel's ongoing genocide of Palestinians specifically.