I know we are comparing 2 different technologies, but I would like to know pros and cons of both. WCF is present for almost a decade now. Didn't anything similar exist in java world until now?
At a very high level they would both appear to address the same tooling space.
However, the differences I can pick up on:
In short:
GRPC seems a much more focused services framework, it does one job really well and on multiple platforms.
WCF much more general purpose, but limited to .net for the time being (WCF is being ported to .net core but at time of writing only client side functionality is on .net core)