Yes, all level crossings in the game are permanently closed. This is to help prevent lagging. Matt said it is something they want to change in the future.
SPG was the only route in TSW that had working crossing gates. This was because after the initial release of TSW, DTG found that the crossing gates were causing performance issues, so working crossing gates were never used again. They know how to fix the issues so the gates can work without slowing down the game, but with the release of TSW2, there are bigger things that have to be addressed, like fixing bugs and moving over the preserved content, that take priority over making the crossing gates operational.
If they do make the gates fully functional the gates on SPG often activate too early on TSW and it makes them lower minutes before a train comes. Which they should activate at least 20 seconds before a train comes and they should raise just after a train passes over a crossing. The gates raise when a train is far away which is often unrealistic