I don't understand how apple.com can rank over youtube.com? In what way is apple a daily service that people must access? I guess some apple service that I don't use like music?
Probably apple telemetry. At least some of the phoning home is done using apple.com as a domain so it can add up very quickly. If anything I'm surprised the top domains aren't just telemetry endpoints, but I guess telemetry is a good use case for bare IPs so it doesn't show up as much on DNS analytics.
Cloudflare only has access to DNS requests made to their resolvers, not the amount of bandwidth utilized (which would certainly push Netflix and YouTube up) or the number of requests made. They also have some vaguely defined fudge factors to their rankings.
To take a guess at why Apple is so high, I think bundling all of these together might help their rank:
- App store downloads
- iOS updates
- Apple TV+ streaming
- Services that iOS / tvOS / macOS devices utilize
- Apple Music / iTunes downloads
- iCloud (including Private Relay and related traffic)
Sounds like those would provide rather biased samples because changing your DNS server from whatever you get from your ISP via DHCP is something that approximately no normal person would ever do.