The difference is that those missiles are expensive multi-million dollar munitions, while these drones are mass produced for less than $20k/unit and yet are still capable of taking out heavy armor.
Also you're still not remotely competetive with drones that can be carried and operated by infantry at that price point. Who's going to do reconaissance so you even know where to strike before you fire that missile? A drone provides all of that in a package that'd still be less than 1/10th the cost.