I think this all reflects on under-investment in NI as a whole, but undeniably the NW in particular. BFS should be much more accessible to NI's second city than it is (in lieu of LDY having a larger route network). The train line goes pretty close to the place, so a railstop is a no brainer.
The line does indeed go right past BFS, but no trains use it anymore.
Since the Mossley Viaduct re-opened, it's been quicker Belfast - Antrim that way rather than via Lisburn and Aldergrove. There are some more trains due for delivery next year, which should replace all the slam door and Larne Line trains. But a new station at BFS would cost hundreds of thousands of pounds (they're very expensive things to build, in terms of accessibility and the endless regulations relating to railways) *and* you'd have to persuade NIR to invest in a new service (Belfast - Lisburn - Antrim) in addition to the existing services. Plus it's almost all single track so a nightmare to schedule convenient clockface departures.
On the ongoing debate re: the appeal of BFS/BHD vs DUB, it's worth noting that Aircoach are quitting the Belfast / DUB run even sooner than they previously announced. The last bus runs on Wednesday, not the end of the month as previously announced.