Most of the pokemon in this generation are either slow as dirt have taunt or resist it, plus dragonite will most likely lose ms after 1st or 2nd turn. That leaves it with roost and dragon tail and with meh attack power and that being it's only attacking move it won't be doing much.^Some of the main points of that set included spreading paralysis and using Roost to heal yourself up and reactivate Mutliscale. As you already acknowledged, Garchomp can't do any of that, so how could Garchomp "do it better"?
In my opinion: I feel like it's more like a big wall that's not doing much of anything. Garchomp has a way to spread sr around while racking up some decent damage and still being decently bulky.