It could be. According to bimmerprofs (and BMW) desulphation happens when you drive 110km/h for 25 minutes with more than 50% fuel (!). So if you never drive on autobahn, it will get glogged:
https://bimmerprofs.com/30ea-nitric-...r-sulphurized/
Since the NOX converter anyway will go bad with mileage, I believe the cheapest solution is an emulator. Easy replacement.