Not really. When Steel and Dark-Type were introduced they only changed a few things. Magnemite and Magneton's Type, Bite became a Dark-Type move and that's really it. I could be mistaken though. Also, who said they have to change anything besides the type match ups? Why would they need to change the types of prior moves?
They only changed a few things because Pokemon only had a few things. There are so many more Pokemon and moves now, it would require major re-balancing now to make it all work correctly. If GameFreak just wanted to add new types 'for the sake of adding one' (read: torturing themselves) they would have done so by now, when it was easier.