I also still have this issue, restarting in safe mode doesn't solve it anymore. Anyone found a new solution, or does updating to Tahoe fix it?

For anyone also having this issue: Starting my mac in safe mode and then starting normally again fixed it.

The solution from Hablo also worked for me and broke the MacOS settings. What completely worked: Starting my mac in safe mode and then starting normally again, for some reason that reset the GPX file handling.