Helm uses gRPC. When gRPC made their 1.4.0 release they made an important change that wasn't obvious from the release notes. Prior to 1.4.0 there was one function of MaxMsgSize. In, and following, the 1.4.0 release this function was deprecated and there were two new functions of MaxRecvMsgSize and MaxSendMsgSize. Where MaxMsgSize had previously set the size on both send and receive it was now just set the receive value. This was a change in behavior.
This example is somehow clearer than the entire @sdboyer essay.