Just sharing a method to download GPX tracks with API V3 for those that haven’t seen. Sequences can be downloaded in the GPX format using this call.
One example would be:
curl -H "Accept: application/gpx+xml" "https://a.mapillary.com/v3/sequences?bbox=106.20208740234375,47.431803338643334,107.74841308593749,48.350773448467294&client_id=<CLIENT_ID>" > sample_sequences.gpx
Bounding box format is mix,miny,maxx,maxy.
You can also user other parameters like the sequence ID or the username.
Credit for @tao for building this into the API.