During the 1940s and 1950s, I particularly remember how difficult it was to open train doors from the inside.
There was no central locking mechanism to prevent doors being opened while the train was moving, so I suppose it was sensible to make the latches stiff for safety reasons. There were certainly notices up about not opening doors until the train came to a standstill.
In fact, passengers in a hurry, always did seem to open the door and jump out while the train was still drawing to a halt on a platform, but they must have been fit anyway or they could never have managed to get the door open.
In 1955 between school and National Service, I needed work. One job was to clean train carriage handles with pumice stone. The handles were brass and I was instructed by the regulars to clean what showed only. Thus the front was shining and the rear of the handles was somewhat mucky.
The old films often added drama by showing people being thrown out of or jumping from moving trains, and this was certainly possible in theory. However, the latches were so stiff that I for one, even as a teenager, needed both hands to open them.
Some of the 'newer' trains had door handles that only opened from the outside - which was, I suppose, to improve safety. It meant, though, that if no-one on the platform wanted to get in at a particular door, and passengers wanted to get out, the passengers had to lower the window and lean out to get to the exterior handle.
So opening this type of train door was a dirty business as the inside of one's sleeve had to go tightly over the open and invariably sooty window, and it also required a certain amount of strength. When I needed to get out, I would walk along the corridor to find a male passenger with a long arm waiting to get out, and let him lean out of the window to open the door.