Don't forget, we can only do this sustainably and at decent capacity for less than half of each solar day, and we have to eat, rest, and sleep. So it should naturally scare you just a little bit when a machine can approach human levels of I/O, but be maximally efficient as long as there's enough electricity (which we'll soon have via small nuclear plants next to every AI data center).
I agree some of it may be people's insecurity and/or religious and philosophical questions, but some of it may also just stem from pure survival instinct.