Always about money, corruption
It's quite likely that this proposal is coming from "cyber" security lobby groups who know that their industry could grow tenfold if they are allowed to work the offensive side. Fat official government contracts, mercenary arrangements, and limitless commercial vigilante work. Hell, they could even play both sides. The industry is already swimming in cash, so the chance at a significant increase I'm sure justified quite large campaign donations, enough to convince these representatives to present such laughable legislation. Given the shift in american politics, playing to the ignorant in the extreme, they just might get away with it.