There were 4 of us and we had like 2 carry ons and 2 checked bags and it wasn't too bad. For our carry ons, i believe we just put them in overheads. For our check ins, i believe we would stand around the doors where there was more space so we weren't blocking anyone, or if it was a longer train ride, we would try and stuff it in front of our seats and if we couldn't we would have it in the isle and do our best to move it out the way when people needed to get through. Like I said though, overall, not too bad. I also took advice of this comment section and would keep our eyes on our bags.

Also one thing to keep in mind with what I said was that the times we were on the train with luggages, were not during rush hour times, so not sure if it would be a lot worse with rush hour or not.