While I don't use Organic Maps as my daily driver because there is no traffic data, it has been invaluable to have on my phone. It is one of the best offline and trail maps I've used.
1. Much traffic data is private / requires licensing, however some countries have reasonable public data. For example the TraffXML (https://gitlab.com/traffxml) project has some.
2. The project is free to use, but also volunteer driven. It requires setting up a privacy preserving "live data" infrastructure.
If you think this is a nice challenge and you can help, feel free to reach out!
https://github.com/organicmaps/organicmaps/issues/1160 would be a good starting point.
For me the winning feature is the UX around dropping a pin and routing to it via trails just works and is very easy, and includes elevation gain etc. Too many hiking apps require you to navigate along fixed trails in their hike database.