We bought this home/property in 1987, and it featured the 3 hardwoods in the front yard, and 4 mature hardwoods in the backyard ( a giant white oak, a large red maple, a magnolia, and a tulip poplar). Quite shady (and energy efficient as you suggest). And going forward here in Charlotte (“the City of Trees”), further tree maturation meant about 5% more shade every year.
I started the palm gardening in 1992, with 2 tiny windmills in the sunny grass strip between my driveway and my neighbor’s. Then, I read that Needle Palms like the dense shade. I got the Palm-Planting bug. Then got adventurous and tried the Med and Pindo palms - but everything I read about them said the only chance for survival here at 8a/7b was planting them against the south-facing house wall (in the deep shade, in my case). Two other Windmills were planted in the shadow of the big white pine - and they did OK, but were leggy.
5 years ago, my red maple got diseased and had to be removed, and earlier this year, the white oak met the same fate. The backyard environment changed from being Costa Rica-esque to being Phoenix, AZ-esque. The thought of writing a 4-figure or even a 5-figure check to take out other healthy hardwoods does not compute with me. Meantime, neighbors to the right and left both took out major hardwoods in the last 2 years and that has helped a lot!
So, yes, I most certainly recognize that more sunlight would be far more palm-accommodating, but I’ve been playing with the environment dealt to me.