Not a word about Thrift, perhaps it was too low level for an infra overview, but I would have expected it to make some technical impact from a global perspective.
I wouldn't be surprised if they have switched to GRPC for improved performance. They mentioned that RPC libraries are centrally maintained in their monorepo; a migration from Thrift to GRPC might have taken less than 6 months.
gRPC and Thrift are comparable in performance and there is actually an opposite trend of switching from gRPC to Thrift in the few places where the former is still used.
I participated in a painfully slow migration from Thrift to gRPC. I did not record the performance metrics, but it was internally advertised to be significantly more performant. There are still some Thrift services running at the organization, but most were migrated to gRPC and certainly not migrated back.
I haven't been there a while, but that is extremely unlikely.