Spamming me via private message certainly ruins my enjoyment of the network.
And which section defines "spamming" as "sending a single message throughout the entire duration of a pilot's flight"? I got one of these whilst flying as well. Read it, decided it wasn't for me, closed the PM, went about my flight.
Sorry, but if receiving a single PM that you can read at your leisure and decline to take any action on if you're not interested can "ruin [your] enjoyment of the network," then maybe the network isn't for you. And by "the network", I mean not only VATSIM but the Internet as a whole. If there's a decision (from those in positions to make one) about how the PM functionality should or shouldn't be used, then let that decision come to light in the form of a clear PM usage policy.. not this "oh but it ruins my fun!" crap.