Oh wow that's incredible of you. Thank you for your efforts.
It's 90% there, there is only one small thing missing to make the functionality perfect for sticky tall sidebars, and that is that when you scroll half way down the page, the sidebar should stay frozen and be "scrollable". As in, if you scroll down to the middle of the page, and then scroll upwards again, the whole viewport scrolls but the sidebar stays until you pass the top edge again and it becomes sticky at that point again. And if instead of reaching the top edge of the sticky element, you start scrolling downwards again, it still stays frozen until you hit that bottom edge and at that point continues being sticky.
You can see this happen in the sticky sidebar script example I shared - this functionality is the only reason theme developers like me use popular scripts like Sticky Sidebar, HC Sticky, Sticky Kit, etc instead of just using "position: sticky". If ScrollTrigger can do this, I'm sure everyone needing proper sticky sidebars would flock to using it.
Hope my explanation makes sense and thanks again