I am certainly not against shooting a heavy bow. I shot bows in the mid-60#s draw weight myself for a few years and could still work into that weight. If you prefer a 60-80# bow and shoot it well, that is good.
I dropped 10-15#s for a couple of reasons. Awkward shooting positions when hunting is one. As long as I could stand pretty much square to the target and use the same muscles that were toned up well for shooting I could shoot my 65#er with fine accuracy and yes, I too seemed to get a little cleaner release with the heavier bow.
But when I try bending forward to shoot under a tree limb, or turning to shoot to the right, (in the case of a RH shooter), to shoot slightly across the body, or any other "non-standard" shooting position, accuracy would suffer because I was using different muscles.
Also, the bows built in recent years simply have a little more zip. I have a '66 Bear Kodiak that is 52#s and a beautiful bow. I have a copy of a mid-late '60s Kodiak that is 50#s and has a slightly different limb design with bamboo cores. I don't own a chronograph but the newer version is obviously faster than the original.
The last two deer I shot were w/ bows in the 50s draw weight. One w/ a 54# Shrew that was a pass-through that still had enough steam that the cedar arrow stuck in a tree behind the deer. This year I shot a deer w/ a 50# Red Wing hunter that the broadhead passed through but the fletchings hung the arrow up on the hide, but this was at 35 yards.