The poll is accurate, IMHO. Americans most dislike Iran for two reasons: (1) What Iran did to our diplomats in 1979 and (2) what Iran does to threaten Israel, and, therefore, cause we Americans to have to defend Israel.
I, myself, as a 67 year old American, educated in an US Ivy League college and having a PhD in Physics, hate only one nation in the world: Iran. I would support the USA mounting a total annihilation of all of Iran's nuclear facilities, and the decimation of all of Iran's military facilities, regardless of the collateral civilian damage that would be caused.
P.S. Qom should also be wiped off the face of the earth.