Please do not deprecate OtlpGrpcMetricExporterBuilder#setChannel

As we can see, OtlpGrpcMetricExporterBuilder#setChannel has been marked as deprecated.

  /**
   * Sets the managed chanel to use when communicating with the backend. Takes precedence over
   * {@link #setEndpoint(String)} if both are called.
   *
   * @param channel the channel to use
   * @return this builder's instance
   * @deprecated Use {@link #setEndpoint(String)}. If you have a use case not satisfied by the
   *     methods on this builder, please file an issue to let us know what it is.
   */
  @Deprecated
  public OtlpGrpcMetricExporterBuilder setChannel(ManagedChannel channel) {
    delegate.setChannel(channel);
    return this;
  }

In our case, we have the need that put multiple ipv4/ipv6 addresses into one ManagedChannel rather than using domain name directly. To achieve this goal, we also customized the corresponding load balancing strategy in gRPC.

So I don't think OtlpGrpcMetricExporterBuilder#setEndpoint is universal enough.

Start with OtlpGrpcMetricExporterBuilder#setChannel and compare it with setEndpoint(String), including the documented precedence and deprecation text. Determine whether the reported ManagedChannel and custom gRPC load-balancing use case can remain supported; done means the project has a decided, documented outcome for the deprecation request.