In the Pacific Northwest, the extra length is necessary for the tree diameter, not the tree distance. When I began hammock camping, I went up to a tree and figured out what the maximum, comfortable, vertical reach would be for me. Note that the further apart the trees, the higher you have to reach to stay in that 30° angle zone. With that information, I knew my preferred suspension length, plus what was necessary for the tree diameter. Much later, to my chagrin, I realized it's the tarp, not the hammock, that designates the distance.
For simplicity, I use a daisy chain and a carabiner for hammock suspension. That's because I am often responsible for more than one hammock setup and with the carabiner it's "clip and no concerns", rather than having to check a bury. I'm strong enough to deal with a few extra ounces. And, for full transparency, I'm more often kayak camping; weight and bulk are less of an issue.
Pacific Northwest Trees
View attachment 11