Seems like we go through periods of hyper-growth when the conditions just happen to be right for what appears to be accelerated growth.
As for reports of the poison ivy being more toxic, it may just be a case of forgetting how bad your last case was, or not having been exposed for awhile and your body reverts back to a basic level of tolerance of this plant.
I relate it to how people complain about the weather, and forget about the last few years of storms and winters we've had.
I know, I'll chock it up to people becoming "de-sensitized" by overt internet usage. They spend so much time indoors and "hooked up" to their electronics, they completely forget what the outside world is really like!
