Further, to hack a 3-4Gh/s network, you need to know a pool with over 2Gh/s, which I would like to see anyone have before ASIC comes out. (that's 2000 x R9 290x at max config)
If you want to worry about Worldcoin being hacked, you have a LOT MORE to worry before that I think.
When do you think the new ASIC's will come out and how high a hashrate do you think one person could get with a lot of them?
When pools started destroying coins Kimoto invented his gravity well to neutralize the threat. Is it possible someone could invent something to neutralize the threats posed by the new ASIC's?
I know Kimoto's gravity well is not perfect and people on this forum are talking about possible attacks they can make on coins using it, but it's a start at defense.