I think the focus on Overture is going to be on machine-generated data like imagery-based mapping. Unfortunately it isn't really super practical to feed this kind of thing back into the OSM project right now (extremely high change rate makes it hard to review changes, OSM process for approval of automated imports is oriented towards a high level of reliability that this data doesn't always have). I think maintaining this kind of data separately from OSM but still permissively licensed makes a lot of sense, and will benefit the OSM project as these data layers will become useful sources for the manual, human-intelligence-based mapping that the OSM project is really built around.
Or to put it a little differently: from my experience with OSM politics (not expansive but also not that small), the OSM project probably doesn't want this data. It would become a huge headache for OSM contributors to do QA on. There have been multiple notable incidents of companies starting to feed automatically generated data in to OSM and getting lambasted for it. Keeping it separate from OSM but available for use with and for OSM is the respectful thing to do.
That's how I view this too. Increasing the 'demand' for OSM's data will be a net good since it guarantees a future where companies are using it and reliant on it. Not burdening them with all of this extra info that they don't want and can't reasonably steward makes a lot of sense. It's hard to see how this is anything but a big plus for the OSM community.
Or to put it a little differently: from my experience with OSM politics (not expansive but also not that small), the OSM project probably doesn't want this data. It would become a huge headache for OSM contributors to do QA on. There have been multiple notable incidents of companies starting to feed automatically generated data in to OSM and getting lambasted for it. Keeping it separate from OSM but available for use with and for OSM is the respectful thing to do.