Plants make more leaves than they need in case a deer eats some or a hailstorm ravages across the sky and hurts some leaves, etc...
But there is always that limit on both ends of the spectrum where too much or none-at-all keeps the plant from maximum yield.
Photosynthesis is the source of energy the plant needs to make food (sun + minerals = sugars/energy) and all that happens in large, green leaves. Especially mature green leaves that produce more photosynthates than they consume, turning themselves into powerhouses for the plant. The plant needs mature green leaves to make an over abundance of sugars & energy, otherwise it's just surviving, not thriving.
Personally, I don't see that buds need light to grow. The plant naturally grows towards the outside anyways, like a fruit tree, but you can still pick nice oranges inside the canopy.
You might be looking for a different example but here is a plant with essentially 10-15% defoliation/pruning throughout her life just to help crowding and balance. When I did the harvest defoliation 1st round she looked like this and you can see a decent amount of trichome encrusted buds towards the bottom.