Every DNS company I’ve worked at (which includes the one mentioned here) has at some point informally kicked around the idea of being a general key/value store. I think it’s a natural thing to happen upon when thinking about where to grow the business outside of DNS - first there’s the “let’s rack some caches” (CDN), then there’s “let’s sell the network” (VPN), and then there’s “well DNS is basically an eventually consistent key/value store.”
It is very niche. Fun idea, but not widely practical. Your data needs to be public (DoH/DoT is only last mile), your data needs to be okay with being tampered with (can’t rely on resolvers validating DNSSEC), your data needs to be extremely read heavy, your reads require a global footprint, and you can tolerate periodic outages for writes (even though every DNS company worth its salt has a 100% uptime SLA on the dataplane, no one has that on the control plane - expect control plane latency to vary from seconds best case to minutes/tens of minutes during significant outages/DDoS).
I did this to keep my VPN token somewhere all of my servers could grab it without additional tools