Delay assigning new replica shards

Whenever I tweak the following settings.

PUT _cluster/settings
  "persistent": {
    "cluster.routing.allocation.balance.threshold": null,
    "cluster.routing.allocation.cluster_concurrent_rebalance": null,
    "cluster.routing.allocation.node_concurrent_recoveries": null,

I've noticed that newly created index will have the replicas in "unassigned" state for a long time until existing rebalancing is finished. Has newer ES releases fix this?
We are running version 8.10.2.

It seems silly that new shards assignment is in the same queue as rebalancing existing shards.