Well, we don't need to keep re-inventing the wheel...but each generation wants to experience the wheel-inventing for them themselves...and I think that's fair.
I think it's unrealistic to cocoon ourselves and keep ourselves so safe that our lives focus only on taking the next breath and nothing else.
Of course care has to be taken...but there are two kinds of accidents, avoidable ones and unavoidable. If you've taken all reasonable precautions, then I chalk up the unavoidable accidents to life.
If you really want to make the world safe, you have to get rid of all cars, electronics, varnishes, carpeting, particle board, medications (side-effects), booze, sports, dining (you might choke on something)...etc. to the point it just gets silly.
Our acquaintance that died 2 weeks ago? We still don't know all of it, but it looks like she misstepped and fell down the stairs when she went home at lunch to pick something up before returning to work. Her house was under construction and their was no stair railing. So add home renovations to the list.
I'm much more likely to die tonight on my way home, in a car accident, than ever by an errant cannonball.