You'll probably get various opinions in this. I don't provide any light so that's where I am coming from. I don't depend on selling eggs so I can allow them to stop laying. Besides, I always have some pullets that started to lay in late summer or fall. These may slow down a little, especially when it gets really cold, but normally these lay all winter without light so I don't run out of eggs for my use.
I find that the egg shells lose a lot of color the longer the hen lays. After the chicken molts, the egg shells are back to a real pretty brown. They just look better. They are also noticeably bigger. I've read that the number of eggs that are laid drops if they go a long time without a molt. I have not really noticed that, but I only have a few chickens. If I were a commercial operation with thousands of hens laying, I'd probably notice.
Commercial operations don't keep hens laying forever. They control the molt by controlling the light. It can vary some, but a normal sequence is to keep the chickens in mostly dark until they are old enough to lay decent sized eggs. Then they switch to 14 hours of light to get them started laying. After a while, they force them to go through a molt to get the larger eggs. They make more money with the Grade A Large eggs so that is the target. Then they let them lay for a year or more without a molt. But at a point, they either feed them through another molt or get rid of that batch of layers and bring in fresh chickens. If they could, they would keep the chickens laying for several years solid without a molt. Whether it is number of eggs or egg quality that drops, and I suspect it is both, they find it more cost efficient to get rid of that batch and feed a new batch of chicks up to laying age or feed them through a molt while they are not laying than to just keep going.
If you are looking at longevity in your hens, I think a molt really helps them. If you are going to replace them when they get inefficient, adding light probably makes sense. It depends on your goals.