There are a few tiers of hosting providers ranging from "We rent you server space", "We rent you a physical server with internet access", too "We rent you a VM"

There are a few tiers of hosting providers ranging from "We rent you server space", "We rent you a physical server with internet access", too "We rent you a VM" or "We rent you services you may want to access". The privacy angle of self-hosting generally ends as soon as you are renting a physical server with internet access. Someone else has access to the hard drives, the network traffic, the hardware, and via hardware remote access the OS/Data. At this point you would need to trust the legal bindings on what the hosting company can and can't do to your physical machine. One really exciting angle on end2end encryption is that your provider may be technically incapable of any malpractice (for better or worse, I may wish my provider could have a sys eng bail me out every now and then).