Earlier quoted context omitted.
> They are not a general purpose VPN service, and can't even be used as one. I'm not sure what you mean by this, but this sounds like exactly what they are, with some functionality on top. It's what I use to VPN into my LAN from outside, and it's pretty general purpose from where I stand.
I'm talking about services like NordVPN, Mullvad, etc. They do not funnel your Internet connection through their servers.
Those are not general purpose VPNs though.
In fact, they are not even VPNs in the first place. They merely use the same technology to provide a private tunnel to the public Internet (and use the name in marketing material because by now people are familiar with it).
What they are not is general purpose private networks.