It was certainly different, but I wouldn't say the original art style was 'destroyed' due to the fact the at any time in the game you can switch back to the original style. It's not exactly destroyed if its RIGHT THERE.

I think with DotT there is less room for that kind of art upheaval though, because, frankly, the art already looks good. It still holds up very well today, expecially if you run in SCUMMVM in turn on some graphics filters.