Presumably will lose some auto-discovery of new things added to the network. In my case though, I added some Kauf WiFi smart plugs after making that change, and they were quickly recognized by HA without issue.
I voted for and made a comment to this existing feature request to offer an ability to toggle it off without having to resort to using HACS.
https://community.home-assistant.io/t/dhcp-add-configuration-options/677111/2