What (if any) are the implications of the recent Supreme Court decision in Oracle v Google. It sets precedent that APIs are fair use. But how does this work with GPL?
Specifically, imagine the following scenario. I create a library A that uses library B. Suppose library B is released under GPL. My understanding of GPL (and please correct me if I'm wrong) is that it requires library A to be released under GPL. But if all I'm using from library B is its API, then why can't I, under fair use, release library A under MIT? When a user compiles the code using library A (and B under it), then the compiled code has to be GPL, since it's including more than just the API of library B. But it seems like the source code to A itself could be any license I like. After all, one could one day create a library C that implements the API of B, but is itself MIT. Then user-compiled code that includes A+C could remain MIT.
Is my thinking on this off, or is it really the case that my hypothetical library A could be released under MIT?
P.S. This questions is related to, but different from an earlier question about the case. The obvious difference is that the Supreme Court decision is new.