I’m pretty sure this way they’ve hardcoded the NTPs is actually against the ToS for use of the NTP pool too. The way a vendor embedding NTP is _meant_ to do so is documented here: https://www.ntppool.org/en/vendors.html On another note, back when I ran a web hosting business we hosted a few NTP servers in the pool. It’s such a simple thing to give back, and worth anyone who can make a stable contribution doing so.
> The pool is currently keeping the time of an estimated 5-15 million systems accurate. When was this page last updated? I would expect that number to be in the hundreds of millions these days, perhaps even billions.
> Do not use the standard pool.ntp.org names as a default configuration in your system
Apple's default is time.apple.com, ubuntu has their own pool, android as well, same for windows.
All the big linux distros also run their own ntp servers.
The ntppool.org stats show about 100k queries per second https://status.ntppool.org/
100k/s is consistent with on the order of lower 10s of millions of devices, with most checking every 10 or so minutes, and a few misconfigured ones hammering the server at a high frequency.
It certainly isn't billions of devices.