I'm a unix/network admin. People don't really think about it or realize that they put a tremendous amount of faith in thousands of admins all over the place that have root/admin access to their data.

Guys like me at say a company level... we are god. We know all... see all. Its not a joke or a trope from a movie. Its a basic truth. When you go up a level to the guys with the root/admin password to a DNS server(which this appears to be the OP case) or a server farm doing data storage or even the guys who work on backbone routers. Their little section might not see all, but what they can see they have unlimited access to.

I guess what I'm saying is people subconsciously ignore that they are trusting these people not to abuse that power. A root/admin password on a server/router like that is far more dangerous and powerful than say a firearm. Would you trust that stranger to stand 5 ft from your child holding a loaded rifle? But yet you trust him not to go and copy pictures of your half naked daughter from her phone cloud account. You're an idiot.

Then who can't they spy on???

If you are referring to these big tech CEOs etc... the answer is they can and DO spy on anyone they want. There are no checks and balances etc to prevent them from looking at your data. MOST people are only safe because they are just a rando in the crowd. If they have a reason to target you like the Trump family then you are not safe AT ALL.