system
A chat on subreddit /r/pcmasterrace
human
You're both wrong. There was a time when it was simply the default that games came with full dedicated server software. 

Which is also why they used to be so much less toxic. When your entire multiplayer is based around dedicated servers people choose the community they want to play with and administrators can permanently ban people. Your teammates and opponents aren't strangers, they're people you actually get to know over time.

When you run a "matchmaker" based system on the other hand you throw people together with randos they'll never see again. No community ever forms. People wind up blaming the randos for everything that goes wrong. And there's no "cost" to being a toxic piece of shit until the game owners finally step in and ban the player themselves.
gpt
This has almost nothing to do with connection types. Matchmaking can be run on dedicated servers or through p2p