Imagine all the people you walk past you don't hear because of your headphones, a task only challenging for those who don't use them (much), but please try.
For me, they're not a tool for isolation, however, it's a nice additional perk. Still, when I hear a stranger asking for attention, I anxiously give it to them.
This one time, a guy in his 'parked' car at the side of a street in Den Bosch told me that because the car hadn't moved in months, the battery died, and he asked me if I could help push start it.
I didn't have anything better to do, so skeptically, I helped him. Together, we revived the car, and while honking, he drove away.
Another person that I'll likely never come across, and even if I did, I wouldn't hear or see.