Primary question: Is there any way to navigate to the bottom (newest posts) of the top replies summarized thread?
Different than having to swipe scroll down manually through all the replies of course.
Secondary question: Is there any way to customize thresholds for the top replies thread summary function?
Hover over the scroll bar and you can swipe/drag it all the way to the bottom in one fell swoop.
You are right, although I have to switch from mobile view to desktop view to be able to do that.
In mobile view, the usual access to the scroll bar is blocked by the top replies viewing banner.
And toggling from desktop view back to mobile view unfortunately switches back from top replies to all replies as well 
(Vivaldi Browser on Android)
