I see both sides. Part of me thinks one of the best things Dreamworld has is their Disney-esque architecture. It's certainly not a decades old Waikiki super flip or ToT. I'd like them to try and hold onto something connecting them to their heritage, but at the same time, not at the expense of progress.
For example - on the ground that now sits Space Mountain in Disneyland, there was once a hover-bumper car attraction. This attraction was revived for Cars land circa 2013, but has already been removed due to capacity, reliability and experience. If we held onto that Tomorrowland attraction simply because it was the first in that space (Disney historians, I know it wasn't THE first attraction on that spot, but prior to that was the circus I think, and that isn't really tomorrowlandish - if I'm wrong, meh, I'm going from memory). The point is that not everything does need to be held on to just for history's sake.
Wherever possible the park should be sensitive to its history, and honour that where they can (so, for example, the new exit doors through the Emporium are just ridiculous), but in terms of the I-ride, whilst it suited the 'cinema' style of attraction very well, and fitted on the previous 'main street' - that 'main street' is slowly disappearing, so to keep just that one building in original condition would then look very out of place.
Further - we have no idea what the ride theme is yet. Although unlikely it could take on the 'Soarin' look of an airport \ runway \ hangar façade - for which of course an old school southern colonial style building would look completely out of place. Likewise - would we have cried foul if they'd left Wayne Manor when they installed JL3D ? Ok - it has a tenuous connection, but then they'd need the story to get you from the manor, through the batcave and into the JL part of the attraction, and the Hall of Justice (if not somewhat skewed) is much more suited to the attraction.
If it were presented as a 'theatre' or 'cinema' and then once you got in it was transformed into flight, sure, but I find that a hard theme to flesh out in my head. Although it's a shame to see it go, especially with the Disney versions above so clearly resembling it, at the end of the day, history shouldn't stand in the way of progress (which is why ToT should be unceremoniously ripped out too)