The problem we have is that most people have no idea how one's privacy is compromised by little unpublished/under-published "software quirks" like this and they are not understood by most people. I would recommended all freedom loving people pay attention to things like this and educate yourself if necessary.
In my case, I route everything through a trusted VPN. I don't care if I'm studying basket weaving I don't want a lifelong record of every website I have ever visited stored at goggle or anywhere else.
So getting back to this little DNS quirk in Armbian, that little trick would, if I didn't have firewall rules in place to block it, have sent all the DNS requests originating from OMV computer to a commercial DNS provided (clouldflare) who would have stored it for I don't know how long and shared/sold/turned it over to whomever without me ever knowing about it thinking I was using my trusted VPN DNS servers provided by my DCHP configuration. Black mark for Armbian in my book.
Most people forget about DNS requests when they think about privacy. Recording your DNS requests make a nice concise record of everywhere you visited, from where you connected, along with the date and time. This is called a DNS leak!