Takeaway from this:

If you operate your own DNS, choose an NS within the same TLD als the domain you resolve: `example.COM` -> `ns.example.COM`, `example.NET` -> `ns.example.NET`, `example.ORG` -> `ns.example.ORG`

It'd be great if a CDN like Cloudflare handed out matching NS records for their most popular TLDs. This would probably speed up DNS resolution time (a little).

So e.g. `*.ns.cloudflare.com` for COM, `*.ns.cloudflare.net` for NET, `*.ns.cloudflare.org` for ORG, etc.

At least for Cloudflare, I believe they have these domains (`cloudflare.TLD`) for most of the important TLDs anyway. And the actual resolvers could be the same servers/IPs, afaict. It's mostly _just_ the (glue) records.

(I know, nothing is _just_ done on a CDN scale. Like, they'd need to also add the logic for handing out the correct NS names for the respective TLDs, which NS.TLD to fall back on for TLDs that they don't operate their own NS in, how to handle this for their bring-your-own-* customers, etc.)

Yes, I had not realized just how much DNS provisioning choices impacted resolver efficiency.