NASA's Voyager Found a 30k-50k Kelvin "Wall" at the Edge of Solar System

The average stuff is very hot, but there's also basically no stuff out there anyway, so you won't run into enough of it to care.

Imagine that there is one venomous and aggressive snake (in a cute little survival-suit) in some random spot in Antarctica. This means "the average snake in Antarctica" is ultra-dangerous.

But there's only one, and it's almost impossible for you ever to meet, so in practical terms it's still safer than Australia. :p