Automatically converting GPX files to OSM ways is discouraged.
This is not a technical issue. It is not very hard to generate ways out of GPX files. However it is technically not feasible to add them to existing OSM infrastructure in a useful way:
infrastructure:
- GPX tracks will overlap with existing OSM data and with other GPX tracks. It is not possible to automatically detect whether there are two parallel ways or if this is just one single way. Especially in cities where GPS accuracy is low due to high buildings.
- GPX tracks will cross existing OSM data and other GPX tracks. It is not possible to automatically detect whether there is a road junction or one of the ways is a bridge or a tunnel.
- It is not possible to automatically detect which OSM highway class (road, footway, cycleway, ...) your GPX track has.
In other words: You will inevitably create bad data of limited use.
Also, just importing a bunch of GPX ways will just lead to roads without any additional information. You will get a road network without street names, maxspeed information, POIs, addresses and so on.on.
However please note that your GPX tracks are not worthless. You can upload them to OSM so that you or other users can use them for manually editing and for aligning aerial imagery.