Even games that did have a global list of servers, one wouldn't necessarily always play on random servers, but have some favorite servers (often ping-based, which means geographically local, to some degree) and play on those.
Using Counter-Strike as an example: no matchmaking system - relied upon community hosted servers offering a wide range of game modes (official and community created). More competitive matches (pick-up games) were often found via IRC.
Now I dunno...
Persistent servers mean they can have distinct cultures and you get your favourite servers and start to notice the regular players. This doesn't happen with matchmaking so much.
And I think the point about the 50% win rate is important - I am a person and my mood and skill varies day by day, but ranking stats are measuring the account not the player. Some days I wanted to stomp noobs, some days I wanted a challenge, and some days I wanted to turn my brain off and run fy_iceworld. You could also change your name at will if you were worried about your reputation due to any of the above.