One other way to look at some of this (especially with the other comments around whether anything is "truly" owned) is in terms of "redundancy". TFA touches on some of the control/portability side but the thought experiment here is something like: how many people am I depending on? If you owned den.dev and den.xyz as mirrors on separate providers that's one less failure point where someone else has the power to disappear you (etc, all the way through to redundant underwater sea cables, I guess!)