I would say that this law hasn’t a chance of becoming a “law”, but President Trump hasn’t declared his opposition to pot use unequivocally, so “maybe?”
Even if Trump were willing, I don’t see it getting through the Senate.
It really ought to be just declassified federally, and leave it up to the states whether they want to make it illegal or not. Here in Canada, that’s exactly what has happened. Sky hasn’t fallen, trains haven’t been crashing in mass. Since it was legalized, I haven’t seen a single change in daily life that was warned about by people that opposed it being legalized.
You might want to check statistics for auto accidents and overdoses of stronger drugs; I know the former thing showed up when Colorado legalized recreational pot.