I read an explanation (another topic) that explains how to display only 1 single track on the map.
However that option is to open EDIT and to DRAG the gpx file (already in your computer !) to the left part in the EDIT window.
It seems however, that gpx files already uploaded by community are displayed ALL together at the same time!
What a mess !
Neither the owner or anybody else might be able to choose and SELECT ONE already uploaded gpx, in order to make ONE TRACK ONLY appear on the map ??
The same question was asked in other words, but the explanation was no valid answer; because any gpx already on your PC can be opened with any other application and much more easier.
If you are talking about the Public GPS Traces option on the layers menu, that is recent, but people were uploading tracks a long time before then.
I would say the main purpose of uploading a track is as evidence that you actually surveyed the route on the ground. Having multiple tracks displayed is not really a problem from that point of view, as each track will have errors, and multiple tracks over the same way will give a better estimated of the true path, and also of the likely errors.
If you want to recover an individual track, you access it starting from the user that created it, which you will probably know if you care which track is which.
I also assume that the API being used to access the data to plot the tracks also gives access to the meta-data, allowing the individual tracks to be separated.
Please note that tracks aren’t recorded to say that you were there, but rather to say that there is some, two dimensional features, that can be followed, and is worth of mapping.