The result is mechanically the same as far as I see it. Disarm makes them drop their weapon. If you're engaged with them you can immediately take a move to pick the weapon up (or catch it out of the air for style points) or kick it across the room or otherwise put it out of reach.
Not really. A disarm is deliberate and how it's caused is important. If it was in H-T-H then it could be dropped (Engaged Range) or taken or even knocked away. If you are pulling or knocking it out of someone's hand at a distance with the force it's more likely to not just drop at their feet but instead be flung away somewhere in Short Range.
Or have two PCs work in concert, with one doing the "disarm via advantage" while another uses Move to throw the weapon away. My Force-sensitive street rat did just that after another PC managed to knock away the rather beefy shock baton that a First Order Stormtrooper was using to wail away on that PC (pushed just show of his strain threshold in a couple of hits).
Granted, it's generally easier if the Force user has invested enough in Move to be able to do the disarm themselves, but it's not the only option for a Force user to take an opponent's weapon out of play.