it is dangerous of course! that's why they are payed for it, if any one of them would worry about his life, he won't be able to do that job,
the accident was just bad luck/coincidence, if he had crashed into the wall, he would have walked away, it really got much more safe these days.that doesn't mean that big accidents won't happen
I don't know if you saw the accident footagee, but I'm surprised he wasn't dead at the spot. the fact alone , that he survived the initial crash - makes it strong statement how much safer it got,
there are always things that you can't think of ahead though, like when Alonso parked on top of Raikonnen, if the car was going into cockpit more, it could have been fatal crash as well, .. so yeah, still dangerous no matter how much safer it gets
but anyhow, none of this will give Jules his life back (or any other driver) , so we just have to move on.
tragedy of course, but there are so many tragedies happening every day