I guess that we are not quite on the same wavelength about this feature, so I'll go through my thinking...
My starting point is a GPX file that contains landmarks for thousands of pubs in the UK. I would expect to only import this file once within the Explore Landmarks dialog - which is where I discovered the new ordering options (and they work perfectly well). However, once that GPX file has been loaded, all future access to those landmarks is made via the Displayed Landmarks dialog, since I have no need to re-import the file.
Unfortunately, the ordering options are not available within Displayed Landmarks - which is where I would have expected to find them. Also, even if I set a sort order during the GPX import, when I view them within Displayed Landmarks, no ordering has been applied.
I think that the main point of this ordering feature is that it needs to be dynamic, since the relative ordering, by distance, is directly affected by the current location of the GPS. This needs to be reflected, dynamically, within the Displayed Landmarks list.
As an example, I live in West Yorkshire, yet the pubs that appear at the top of my pubs list in Displayed Landmarks are all in Cornwall... that's an awful long drive for a beer
I've just been investigating some walks in the Yorkshire Dales, which has prompted me to think of another ordering option. This would be to order by distance from the current map centre point, rather than current GPS location. So in this particular case, I would centre the map on the start point icon of the route that I was interested in, open up the Displayed Landmarks list, select my Walking World landmarks GPX file and see the description of the route I have centred, as well as other routes nearby. Unfortunately, as things stand, the list remains unsorted so this is not what I actually see, however, the potential is definitely there and it would be a fantastic feature for planning walks.
To illustrate this, I've attached a screenshot showing a start point icon with a displayed route and the route description in the lower half of the screen, which is not the correct one...
