Why so? ProtonVPN explained the situation quite clearly though I don't understand why you wouldn't trust NordVPN. Just because they are advertising? Or 'military-grade encryption'? They aren't misleading really, even if it is a marketing gimmick. And who runs it... Well, it is a caveat with most of the VPNs. Because of the delicate nature of them (cybersecurity service, various jurisdictions and such), you don't really know. It is a matter of trust, more than anything. I know that I trust them more than my ISP, that's for sure.
Running your own VPN doesn't really anonymize you though. And like you said, depends what you want from the VPN really.