Thinking back some years I can remember a guard who used to, if he thought someone had been trying to evade his attention, only release one door on the train at the terminus and then block and check each person off.If the doors are released and nobody has explicitly asked you for a ticket, no.
Even then, I'd be stepping onto the platform so as to not be overcarried.
In any event, staff either allow you to disembark or if they're the ones doing the doors, they'll finish up with whoever they're dealing with and unlock them afterwards. I've never known anyone insist everyone stays put til they've checked.
He had plenty of other habits that would be seen as extreme by modern standards too - in context back then it wasn't at all unheard of to pull the train up at random halts or even still extent former stations to dump fare evaders off, using physical force if necessary. Marchington on the Derby to Stoke line was well known for it.
I think some people underestimate how much expectations in terms of customer service and professionalism from the railway have changed in the last 20 - 30 years or so.