OK admittedly this one did take me a while to notice, Playing NTP on my PS5 I noticed that there are very few if any cars/buses on the route, I saw two at Huddersfield and that was it. Also passengers, There were no passengers for me, I was driving a class 47 hauled train empty from Leeds to Huddersfield and as you can see the platform at Huddersfield is empty. No one around at all. It's been like this since the update for me.
Same on PS4 since the update. I drove a 101 from Manchester to Leeds at around 10:30 am completely empty. Only saw 4 passengers along the whole route. None of them boarded my train.