We now know why ferries were cut in GTA IV, from as authoritative a source as you can get.
A GTA IV beta fell into the public’s hands, thanks to a thrifter who accidentally bought an Xbox 360 that had it for £5. One of the first things fans found in it was a ferry, which hardcore fans knew was cut from the game.
Obbe Vermeij said this about the ferries on Twitter:
The ferries were cut late on. They were supposed to be moving back and forth kinda like a train. We figured there would be too many issues with it.
Mostly the collision and AI of peds and vehicles sitting on top of another vehicle. We ditched them even though they were in the trailer.
Rockstar managed to add a simpler form of ferries in Grand Theft Auto Liberty City Stories for the PSP and PS2, so there were definitely fans who were surprised they didn’t make the cut.
You can watch the GTA IV trailer that teased a working ferry below.