DHT server mode for private network

In Configure a node | IPFS Docs , I see that the recommended setting for private networks is dhtclient. There’s an explicit recommendation against setting the mode to dhtserver.

Please do not set this to dhtserver
unless you're sure your node is reachable from the public network.

Why would I not want nodes in a private network to respond to DHT queries between each other? Given the network is isolated and they can only connect to each other with a PSK (swarm.key), wouldn’t it make sense for the nodes to find content in that network using DHT queries?

Distributed Hash Tables (DHTs) | IPFS Docs appears to state the opposite: While WAN DHT nodes switch from client to server mode based on whether they are publicly dialable, LAN DHT nodes are always servers unless the dhtclient option has been set.