The big companies have their own NTP pools and even implementations.

You can use the public Google or AWS pools if you want. Note that they have their own software, too, so be sure you understand the differences like leap smearing.

Blocking FAANG IPs from the NTP Foundation’s pools wouldn’t hurt FAANG at all. It would only hurt people who weren’t aware and used the NTP Foundation’s pool for things.

Not really. The biggest drain on resources historically has come from things like routers that have fixed NTP servers hardcoded in the firmware and every customer ends up using just that one without even knowing they're contributing to the problem. They also can't be blocked as the requests could come from anywhere.