I still have to understand openstreetmap mapping solutions. It's named open, not free, so I guess providing your own server with osm data would work. Only with FreeStreetMap the data would be infected also.
There's a great deal of competition and that generally results in a race to the bottom. The market leader just removed themselves from the market and the best way to capitalize is stay low and build your userbase.
We won't see price changes by any of these companies. They all want to be #1.
I'm not sure what you mean with "free"/"open". The OSM licence has a share-alike part if you merge your own map data with OSM data. If you just have a map and put points on it, it'd be fine.
[1] https://operations.osmfoundation.org/policies/tiles/ [2] https://github.com/openstreetmap/chef/pull/78 [3] https://switch2osm.org/serving-tiles/
OSM.org doesn't prohibit commericial usage, per se. But if you're running a business, you shouldn't rely on volunteers from another project which you're not paying for.