Google doesn't use osm officially. I don't know the status of Apple, while they may use some data from osm, their map is very different

There are big companies who use it (Microsoft, Meta, Amazon), and they donate money and manpower, they have employees actively working on osm.

You can see organised editing activities here: https://wiki.openstreetmap.org/wiki/Organised_Editing/Activities This is where they should document how they contribute data.

Financial sponsors are listed on the webpage of the foundation: https://osmfoundation.org/wiki/Corporate_Members

About your perception of copying from osm: a lot of data on those maps are contributed by users, who may copy it from osm or may not. This problem is actually as old as mapmaking, the only way to prove they copy your map is to include "trap streets" and see if it shows up in other maps.