See, "free speech", right to protest, and all the other rights that democracy entails is all fine and dandy - until you are a foreigner in another country. For all purposes, a foreigner is often a second-class citizen with fewer rights. And no country (democracy or otherwise) I know of tolerates any sort of political activity by foreigners. Indeed, many countries explicitly state so when issuing a visa that any kind of political activity can result in your immediate deportation.
That said, I am somewhat surprised that Donald Trump and the Republicans haven't learnt the political lessons on how Biden's unabashed support, and even defence, of the ongoing genocide in Gaza by the Israeli-right lunatics in power cost Biden (Kamala Harris, and the Democrats) the US Presidency ( https://politics.stackexchange.com/q/89703 ). There was deep resentment against Biden / Kamala Harris due to the harsh crackdown on campus protests ( https://www.theguardian.com/us-news/2024/may/01/college-camp... ). And the fact that political tensions on this issue is still simmering means that even a single political mistake by the Trump administration could be the spark that ignites this issue in a manner that even the media wouldn't be able to cover it up under the guise of "anti-semitism" or "support for terrorism" or "foreign incitement".