Unfortunately I still get duplicates sometimes. Ideally that would be managed by me and the way I connect source devices, but the reality is there will always be the case of duplicates as I hack together different fixes to cover gaps in various ecosystems (long story, but I can’t fix it my end).
This is how a duplicate appears. It would be great if some simple logic was applied to see if an activity already exists, and either not accept the second activity, or merge them (as already happens with Strava and Garmin I think?)
The logic could just look at the timestamps and duration, and if there is a match of over 90%, then don’t accept the second activity (for example).
But which source do you prefer? I dual record my indoor rides with Rouvy and Wahoo and these would match your criterias. But one want to use the rouvy activity, as it has GPS data, another one will use Wahoo data.
So you must prioritise the sources. If I sync to Strava there will be two activities too.