Didn't say they would, only that they could. Why? Maybe to give their drug runners and favored coyotes a means to get across? Hey, but don't confuse me with the person who said these things were going to turn up all along the border!
On second thought, I would encourage the drug cartels to spend lavishly on American made $1200 tools!
Seriously, it is not very practical to send a mule carrying a heavy backpack full of ganja/heroin/cocaine/whatever climbing on a 18 foot high wall using $1200 tools to pump nails on one side and then jump down on the other side.
Having no barrier is what the cartels like. Much easier for the foot soldiers known as mules.