Well for one thing, without divinity, Jesus would have been a liar when he said that he would resurrect himself from the dead. I face plenty of liars in my line of work; don't need another one in my life.
Ok. But the non-Trinitarians have a different way of reading those scriptures, and because human language can be quite subjective, their reading is plausible too, and in their view, Jesus is also not a liar.
My question is - why is this issue such contentious such that both sides wish to revoke the title of "Christian" from the other, including salvation with it?