why includeMetadataInTimeout could be set only in deprecated api

[Xiangyuan LI]

Hi kafka team
  After check the kafka 2.8.0 code,
seems 
org.apache.kafka.clients.consumer.KafkaConsumer#poll(org.apache.kafka.common.utils.Timer,
boolean) allow user to keep poll records during consumer-rebalance when
use CooperativeStickyAssignor, and allow this behaivor must
set includeMetadataInTimeout = false, am I right?

  But seems this parameter only could be set use the deprecated
api poll(final long timeoutMs), I want to know why do such design, does set
includeMetadataInTimeout=false not a recommend idea?

 thx.