I don't have time to explain to someone for the umpteenth time how this is different, and even within the "well golly Twitter is a big company, maybe it's a public utility" argument, the president is a much more unique position and situation than the average user.
The President could talk about how he thinks we should execute our fellow citizens, or call our political rivals skanks, or tell us that Coronavirus will magically disappear by Easter, or that hydroxychloroquine is a miracle cure, all by standing up his own microblog platform and blast it from S3 or Azure. He could hold his press conferences and bullshit to the whole nation, or set up email distros... all things he has done or could do.
Please, for the love of society and sanity, stop throwing around 1984 references every time someone shuts someone else up. Read the goddamn book.
Protests are fine. Mayhem and larceny, however, are not. Violence against lawbreakers is absolutely enshrined as acceptable, and that isn't going to change for the foreseeable future. There is nothing whatsoever wrong with Trump's tweet, certainly nothing overriding the First Amendment.
Further, Twitter is absolutely in the wrong to portray itself as passing some kind of absolute judgement on the President's views, and in fact that it is above the Presidency. It is NOT a neutral platform.