As the ride height changes, if the end link height or the bar height doesn't change, the bar is starting at an angle under that. 90 degrees to the ground. The pivot point of the bar stays the same and if ride height increases, the bar pivots down at static ride height if the end links haven't changed in length. As the bar pivots, it's length effectively changes, because it's on a single, fixed pivot.
You move anything from beyond parallel, it's harder to move it as you have less leverage typically. As it sits now, the suspension at static ride height has more leverage on the bar, making it easier to move, and from what I'm experiencing, takes the harshness out of the initial impacts from bumps in the road. Maybe that's a better way to explain it, not so much preload, but leverage. And considering I'm running 5th Gen struts that probably have a slightly softer spring rate than factory 4th gens, it shouldn't be riding harsh. In fact, it didn't when the sway bar wasn't fighting the suspension. And now with proper length end links, it still rides a lot better than it did with the short end links.
It was so bad I was thinking about changing struts to something else. The road I live on has been in a perpetual state of construction for the past 1.5 years, and covered in poor repairs from trenches and holes dug to replace wires and pipes and who knows what else. So, I've become hyper sensitive to the suspension setup on this truck the last few months. This change is dramatic enough that I'm not contemplating changing out the struts immediately. Take that for what it is. And it was enough of a difference that the wife noticed it. And she never rode in the truck when the sway bar was disconnected.