It’s funny how I can give constructive feedback and someone will still find reason to bitch about it. I think there’s a condition for that.
Also, there is this show which is like the concept:
Kind of the same idea, but with a mom and son.
Thinking about it; A neat twist would be in the modern world, the guy who was saved spends his life trying to fix traffic safety so that people aren’t killed like the woman that saved him, however this causes a problem since people aren’t Isekai’d as much anymore, resulting a lack of heroes to the fantasy world. So while trying to keep people from dying, he is inadvertently making the MC’s job harder as there’s less heroes being sent to pick up slack.