I'm not particularly afraid of technology taking over the world or destroying mankind directly.
I believe that our reliance on technology is the downfall, and at some point in time: A catastrophe will probably wipe out alot of our technology upon which we rely. This means a breakdown in the subsystems we count on. If a society is too reliant on it and cannot gain food and medicine etc, many would die.
I also find genetically mutating our crops and such a concern. The concern is: That there are things we do not understand about our food and DNA that could cause us to produce a food or genetic stimulant unawares that could cause a mutation of our DNA to correct a missing link, and cause a scenario similar to what bees and bats have faced. in the case of bees; They had (still have?) a problem breaking down proteins and many died of starvation.
But i also realize fear of unknowns can hinder growth. Its just that meddling with the base components that our existence relies on is scary to me.
keep your mind from this way of enquiry, for never will you show that not-being is
~parmenides