"they just keep finding better idiots [than me presumably]"

It's a reference to the quote "If you make something idiot-proof, someone will just make a better idiot." So it's either someone stupid beyond what you can yourself be, or stupid beyond the idiots you have encountered so far

About the ] thing. It only needs to be escaped when it comes after a [ so as long as the left bracket is properly escaped, the right one can be bare.