According to #656 and grpc/grpc-java#6684 (comment), Conscrypt uses Platform's default HostNameVerifier if not explicitly set, which in OpenJDK it is a deny-all implementation. This is problematic as mentioned in #656 (comment) and letting users implement a custom HostNameVerifier is also infeasible (discussed in grpc/grpc-java#6684 (comment)). While there is an option to work around this, which is not to use Conscrypt's TrustManagerImpl. Conscrypt provides API ProviderBuilder#provideTrustManager(boolean provide) to do so. However, its default value of true in OpenJDK is awkward, given that it's default HostNameVerifier is unable to be used. Should it be changed to false?

/cc @ejona86