I did a quick search but didn't find anything solid so i'll bring it back up - was there ever anything concrete about the train's closure?
Looking back on memories from years ago I don't know too many more nostalgic moments from my time at Sea World then waiting at the train crossing waiving to people on the train as they pass by. And i'm by no means a train-lover, but the atmosphere having those sort of attractions in a theme park, particularly a family-orientated park, tend to offer a sort of timelessness that only an attraction that was already a nod to an era gone can really deliver. So much so, sometimes you don't need to ride it, much like teens wouldn't be riding the kid's rides, to appreciate what it offers to the overall experience to guests.
It makes me think what kind of park Dreamworld would be like without its trains, although with Dreamworld, I think if anything they would remove the main train station, replace it with a really lacklustre thrill ride, that way it's as close to the front as possible, and the sort of thrill ride Village Roadshow will outdo within a year anyway, and they would just relocate the train to a smaller, more circular track somewhere as far gone to the back of the park in Australian Wildlife Experience as possible. Oh shi, they've already tried that before.