The Overture Maps Foundation (OMF) is a collaborative effort by Amazon Web Services (AWS), Meta, Microsoft, and TomTom "to enable current and next-generation interoperable open map products". This is their first open map dataset.
I mentioned it in the lemdro.id thread but forgot to add it here!
I'd just also make a plug for OpenStreetMap, which is entirely community-driven and based on fully open data.
With that said, OpenStreetMap can be hit and miss in a lot of areas. The aim here looks to be about having something commercial-grade that isn't from Google or TomTom. It would've been nice to see companies get together to support OpenStreetMap though.