Though we do have freedom of Speech in the U.S. we don't have the freedom to yell "Fire" in a crowded theater unless there actually is one

This is the real issue for ex-president Trump. He yelled a lie which wasn't "fire" but instead "Stop the Steal" but still a lie and many people died or were put in the hospital because of it. Therefore, he likely has liability directly for any deaths or injuries that resulted from the lies he told his followers, before January 6th and after January 6th 2021.