Ok, I did read your other comment, and it does have some good points as to why that scene could be a dropped plot point, but I still think the story is better without it. There was no need to reinforce how much of an exceptionally good person Josuke was, and I think the message about selflessness is way more valuable and impactful than the potential for a wibbly wobbly time wimey arc.

If anything, the guy being badly injured only makes his decision to go look if some strangers needed help, without having any tie to them at all, more impressive. He took the liberty to look inside the car and inferred why an adult would be out with a kid in such bad weather, and concluded it was an emergency.

I guess I was terrible enough at connecting dots to completely miss the foreshadowing, but Josuke's backstory would feel pointless if Araki actually used that idea