More like unknowns about implementation details. Defining in brainstorming sessions how we want a solution makes sense, but I don’t imagine talking about details.
I was referring more about discussing the details inside of an already defined solution, like, for example, trying to use a library, which one we use, or how would be implemented in detail something.
It seems they consider themselves complimentary with OpenStreetMap, as stated on their FAQ https://overturemaps.org/resources/faq/#
I don’t know a lot about any of both projects, but it seems fair.