VPN is a tunnel, not a MITM. It's used to bypass our monitoring and filtering. You're tunneling out of our network into someone else's, which may have more favorable rules.
This is a MITM, because LinkedIn is intercepting and modifying the traffic between the email server and the client machine, traffic which is supposed to only be read by the recipient. A VPN isn't intercepting traffic, it's used to tunnel traffic. LinkedIn is positioning themselves directly between the traffic source and the destination to read and modify the transmission.
