Google reimplemented the same API (which should be legal) but "use" sounds like they called Oracle's implementation of the function
Oracle tried to argue that writing your own virtual machine with the exact same same interface as theirs (even a clean room reimplementatio, or an improved version) was copyright infringement
If Oracle had won, it would likely have killed things like OpenJDK, WINE, Proton, Rosetta, etc. and would have made licensing around OpenGL/Vulkan very confusing (for a few examples)
Out here in Seattle, if you give your two weeks notice as a tech employee to Amazon, and you tell them that you're going to Oracle, they'll just send you home that day. Probably not every team/manager, but it's a thing.