IMO, the Senate got this right. Trump acted irresponsibly, but I don't think he committed a crime.
From the Constitution:
The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors.
The legal definition of incitement:
"to incite a riot", or "to organize, promote, encourage, participate in, or carry on a riot", includes, but is not limited to, urging or instigating other persons to riot, but shall not be deemed to mean the mere oral or written (1) advocacy of ideas or (2) expression of belief, not involving advocacy of any act or acts of violence or assertion of the rightness of, or the right to commit, any such act or acts.
From Trump's "stop the steal" speech:
I know that everyone here will soon be marching over to the Capitol building to peacefully and patriotically make your voices heard.