To enhance compatibility with various GPS units, Google MyMaps now handles GPX files differently. When you download a GPX file, it shows pins at each stop instead of a connected route. To create a route in Google MyMaps using these pins, download the CSV file instead. This process may take more time, but it will generate a route. Afterward, you can add any additional layers to your route.
NOTE: Any route created in Google MyMaps will not be RV Safe and will be recalculated based on the Google Auto algorithm.