Okay, so now address the Google TOS (no extraction) and database rights.
Note that this is a FAQ:
https://wiki.osmfoundation.org/wiki/Licence/Licence_and_Lega...
Note that this is a FAQ:
https://wiki.osmfoundation.org/wiki/Licence/Licence_and_Lega...
Obviously that only covers one specific angle though.
So what prevents someone from extracting all of Google Maps' data to OSM?
You can't assume that everything on Google Maps is from scanning public web sites. Sometimes, apparently, they do some actual investigation.
Plus, Google's not always right anyway! Nothing's more embarrassing than being caught copying incorrect information. So do your own research. Obviously copying info from a public website is fine, but info on the ground is going to be more complete and reliable. (Plenty of businesses are sloppy about updating their websites.)