I generally agree with that, but in the South one may have to deal with cottonmouths / water moccasins. They are incredibly aggressive and I once had to shoot 3 that would not be deterred by throwing rocks and firewood. This was in the water and involved folks who could not easily get away. If only me, I would not have shot them. Copperheads can be cranky too, but I haven't seen one give chase like a cottonmouth. I've seen several rattlers, copperheads, cottonmouths, and even a coral snake out west. In all cases except the one cottonmouth situation they all wanted to GTFO as much as I did.
Stainless revolver with .38 shotshells is good medicine for venomous snakes that won't take no for an answer. As others have mentioned, .410 revolver better. Unless you are close to water you won't have to deal with cottonmouths and for anything else a big stick is just about as good. 99.9999% of the time just let them be.