Both those terms are slippery. "Incitement" as a civil crime is notoriously difficult to prove; of course, impeachment is not a criminal matter but a political one, so maybe that doesn't matter so much. But "Insurrection" is one of those words, like "sedition" and "treason," that people like to throw around for their dramatic effect, but which matter in ways not foreseen by partisan ideologues. Hold off on that thought for a minute, though, while we crunch the numbers.
Over in the Senate, there are going to be fifty Republicans and fifty Democrats. Let's say, up front, that all fifty Democrats are slam-dunk votes to convict in a trial. You need seventeen Republicans to vote to convict. How many do you have? My best guess, by the outrage voiced by certain Senators or their known proclivities, is that you probably have around eight, maybe nine who are ready to convict under the right circumstances. Another nine or so are known Trump diehards who were defending his election cause even as the rioters descended upon the Capitol. That leaves around thirty-three whom you really have to persuade. The House managers need to make a case that can be sold to at least eight or nine of them. Unless you can convince them that they really, really need to convict Trump of whatever the House has accused him of, then this is going to be another exercise in futility.
The first thing those arguing for conviction have to allow for is the fact that a very large number of Republicans back home may not vote again for a Republican who votes to convict. Profiles in Courage notwithstanding, that is a major disincentive to voting to convict, especially if the trial as a whole is overly partisan in its presentation and conduct.
Second, by the time Trump is tried he will be out of office. The precedent for impeaching and trying someone even after he leaves office comes from the impeachment of William Belknap, Secretary of War under Ulysses S. Grant. Belknap was caught in a massive kickback scheme, and tried to save his reputation by resigning ahead of impeachment. The House impeached him anyway, and the Senate proceeded to trial. In the end, he was acquitted though a majority voted for conviction. A lot was said at the time about how unfair it was to proceed with a trial after he had left office, and probably a significant number of Not Guilty votes were because Senators thought the issue was moot, not because they thought Belknap was innocent of the charges. So, yeah, you can try someone who is no longer in office, but the only time it's been done, a lot of people thought the issue was moot and the proceedings vindictive. The longer the Senate waits to try Trump, the more Republicans are going to feel this way, regardless of how they feel about Trump himself. So that's another chunk of votes to acquit.
Finally, there's that slippery word "insurrection." It turns out that the Fourteenth Amendment provides for disbarring from holding public office anyone who had ever previously held office upon oath, if they "have engaged in insurrection or rebellion against the [United States], or given aid or comfort to the enemies thereof" [italics mine]. Now, disregard for a moment that impeachment and trial are political, not criminal matters. If you can once establish that an insurrection has taken place, not merely as a rhetorical complaint, but as an actual fact, then not only can you disqualify Trump for having incited one, you might be able to go after other Republican office-holders for "enabling" him, i.e., voting for things he proposed, defending him from partisan attacks, yada yada. And lest you think this is Fantasyland, there are some progressive legal beagles who have been proposing just this. Now, how many Republican Senators -- even those most angry with Trump, and most ready to do their duty -- will want to vote for something that would give Democrats across the land a hunting license to go after Republican candidates for years to come? Here, the sloppy wording of the House becomes springes to catch woodcocks.
So, given party loyalty or self-preservation, distaste for conducting a Cadaver Synod, and finally, wariness of Democratic goalpost-moving, I'm guessing you won't see any of those thirty-three Republican Senators who haven't tipped their hand voting in the end to convict Trump of anything. Which is a shame, I confess. But if it comes to pass that way, you can blame Democratic partisanship and Democratic bungling in presenting and managing the case just as much as Republican reluctance to convict for the outcome.