If you find this horrifying (and I hope you do, because there can be no moral justification for celebrating murder), then I encourage you to really think about whether we would not be better off without such extremist language poisoning people's minds. We have to try to stop escalating, or the cycle is going to destroy our society.
My conclusion is that you don't mind making apocalyptic statements about actions you think are dangerous to society, which sits uncomfortably with your asking other people not to.
This is a nonsense argument. It is possible that constantly making apocalyptic statements can result in an apocalypse, and saying that people should stop doing that is not contradictory.
The words you use matter. If trump is an existential threat to democracy, he should be assassinated. If you're not advocating for murderous escalation, then stop using those words (for example).
Who/what is defining assassination as a reasonable response to that threat, who/what maintains the list of words which can replace "democracy" in that section, and what happens when someone disagrees with the maintainer of that list?
You can "educate" someone all you want, they will still suffer from all the normal biases and those biases will still affect their choices.
This is why we have double blind trials even though doctors are "experts"
I do believe education on how to effectively engage against an idea which feels threatening is better equipped to handle this apparent fact than bigstrat2003's approach of teaching people to not say certain beliefs because they'd be worth killing about. That doesn't mean it results in a perfect world though. Some may perhaps even agree with both approaches at the same time, but I think the implication from teaching the silencing of certain beliefs from being said for fear they are worth assassinating over if believed true ends up driving the very problem it sets out against. Especially once you add in malicious actors (internal or external).