My neighbors to the south have security lighting that shines right into my yard all night long, and on the west side about 35ft from my grow area is a street light -- and the city switched to cool/blue COB LEDs -- and I've had no hermies. I've had seeds hermie indoors, and the same strains growing outdoors (under the conditions described above) did not hermie. I've never had a hermie in an outdoor grow.
It's just a theory, but I think that its the consistency of lighting that impacts the most. If your neighbor had a motion sensor light that stayed on for 30 minutes every time it was triggered, and raccoons and cats set it off randomly several times a night, I think that would have more impact than it being on 24/7 where the plants seem to adapt to it as part of their environment.