network – Search Domains not seeming to work through DHCP on iOS/iPadOS

I have set Search Domains (DHCP Option 119) in my router, but it does not seem to be working on my iPad.

I can see on the router logs that it is being sent to the iPad along with the other requested DHCP information, but it does not appear in Settings.

Search Domains

It gets sent and is used by Windows (yet to test on Linux), so why not on iOS/iPadOS? Does it work for anybody else?