I also do not recall anyone ever being encouraged to step out on to the road to get cars to stop! That’s lunacy if true. Unless I misheard.

I might also have misheard it, but I recall being confused by the same section you were. In my case, I heard it not as something people are actively encouraged to do, but as a learned behaviour that's somehow meant to make things safer. Only, I'm not sure how that's supposed to work...

edit: ok I just rewatched. He said

When boarding from the kerbside, the rules do say you should wait for the tram to stop before stepping onto the road, however in reality the accepted normal practice is to step out into the lane as the tram is approaching, because this forces the cars to stop.

So, I misunderstood it because I thought it was talking about when getting off the tram. Like, swing out of the tram as it's slowing down. And I was thoroughly confused how that would help anything. Probably because...it wouldn't.

But when doing it while getting on the tram, that kinda makes sense actually. You wouldn't step out right in front of a fast-moving car, but if you make it very visibly obvious you're about to step out when there's a car further away that looks like it might be headed in your direction, it can see you're there and stop in time.

I do a very similar thing all the time wherever I am, when crossing side streets, zebra crossings, etc. Places where the car is supposed to stop to give way, but where there's a high frequency that they won't actually do it. I make every effort to look like I'm about to step out in front of them without caring, while being hyper-aware and ready to stop or step back if they don't actually give way as they're required to. It nearly always works: people who weren't going to give way if I had slowed down and acted visibly cautious as most pedestrians do, end up following the law when it looks like I'm forcing them to.