I use light bc their bodies get a natural break at molt and I like getting eggs. They are provided balanced all-flock feed formulated for birds, so I know their bodies get what they need from a nutritional standpoint. Our flock is made up of heritage breeds (not production), so their bodies aren’t pumping out the eggs every day anyway, they are around 4-5 eggs/week, maybe an individual is up to 6/week or during long daylight days, but in general, they aren’t super high production birds.
As one gets closer to the equator, the daylight length varies less. So the birds there are taking a break at molt, and not because the light exposure is too short. Therefore, they are laying through the “winter”, and not likely dying early because of the “winter” laying.
Last winter, with light, my flock slowed up production anyway. So, my 4-5 eggs/ week layers were more like 2-4 eggs / week layers. Then we had a long run of very cloudy and overcast and grey days (and grey and rainy days) and a few actually stopped production altogether that month! The supplemental light shuts off during normal daylight hours, so the best light they were getting that month was from a 60w bulb in the early hours!
Overall, their bodies produce eggs when the environment is right: light, nutrition, health, known routine (no/low stress, familiar environment).